feat(backend): add communication, tester, admin and middleman modules

Implement step 17 modules: threads/messages, notifications with automation (submission.created, idea.created, grant_call.opened), innovation test feedback, admin panel (submissions, verify, metrics, grant call status), Middleman adaptation and partnerships. Split multi-type files into one type per file and replace object-valued dictionaries with string-valued maps in data contracts (migrations 0006/0007).

backend/Infrastructure/Assist/MiddlemanAssistant.cs

@@ -0,0 +1,113 @@
+using TarninaHub.Application.Abstractions;
+using TarninaHub.Application.Dtos;
+using TarninaHub.Application.Matchmaking;
+
+namespace TarninaHub.Infrastructure.Assist;
+
+/// <summary>
+/// Middleman Innowacji (F-8). Adapts an innovation to a service form for an
+/// institution. Uses the configured LLM when available and a deterministic,
+/// template-based rationale otherwise.
+/// </summary>
+public sealed class MiddlemanAssistant : IMiddlemanService
+{
+    private const string SystemPrompt =
+        "Jesteś Middlemanem Innowacji w Małopolskim Hubie Innowacji Społecznych. " +
+        "Dostosowujesz sprawdzoną innowację do formy usługi dla instytucji (JST/NGO). " +
+        "Odpowiadaj prostym językiem, konkretnie (co/komu/jak) i nie wymyślaj faktów.";
+
+    private readonly IInnovationService _innovations;
+    private readonly ILlmProvider _llmProvider;
+    private readonly ILlmRequestLimiter _llmRequestLimiter;
+
+    public MiddlemanAssistant(
+        IInnovationService innovations,
+        ILlmProvider llmProvider,
+        ILlmRequestLimiter llmRequestLimiter)
+    {
+        _innovations = innovations;
+        _llmProvider = llmProvider;
+        _llmRequestLimiter = llmRequestLimiter;
+    }
+
+    public async Task<MiddlemanResponse?> AdaptAsync(
+        MiddlemanRequest request,
+        CancellationToken cancellationToken)
+    {
+        var innovation = await _innovations.GetAsync(request.InnovationId, cancellationToken);
+
+        if (innovation is null)
+        {
+            return null;
+        }
+
+        var serviceForm = BuildServiceForm(innovation, request);
+        var rationale = BuildRationale(innovation, request);
+        var fromLlm = false;
+
+        if (_llmProvider.IsConfigured && _llmRequestLimiter.TryAcquire())
+        {
+            var profile = request.InstitutionProfile;
+            var userPrompt =
+                $"Innowacja: {innovation.Title}\n" +
+                $"Streszczenie: {innovation.Summary}\n" +
+                $"Opis: {innovation.Description}\n" +
+                $"Etap: {innovation.Stage}\n" +
+                $"Instytucja: {profile?.Type ?? "nieokreślona"} (obszar: {profile?.Area ?? "ogólny"})\n" +
+                $"Odbiorcy: {(profile?.Audiences is { Count: > 0 } audiences ? string.Join(", ", audiences) : "nieokreśleni")}\n" +
+                $"Potrzeby: {request.Needs ?? "ogólne"}\n" +
+                "Zaproponuj formę usługi (co/komu/jak) i uzasadnienie.";
+
+            var completion = await _llmProvider.CompleteAsync(SystemPrompt, userPrompt, cancellationToken);
+
+            if (!string.IsNullOrWhiteSpace(completion))
+            {
+                serviceForm = completion.Trim();
+                fromLlm = true;
+            }
+        }
+
+        return new MiddlemanResponse(serviceForm, BuildResources(innovation), rationale, fromLlm);
+    }
+
+    private static string BuildServiceForm(InnovationResponse innovation, MiddlemanRequest request)
+    {
+        var audiences = request.InstitutionProfile?.Audiences is { Count: > 0 } values
+            ? string.Join(", ", values)
+            : "odbiorcy wskazani przez instytucję";
+
+        var area = request.InstitutionProfile?.Area ?? innovation.ChallengeId;
+
+        return $"Co: {innovation.Title} — {innovation.Summary}. " +
+               $"Komu: {audiences}. " +
+               $"Jak: wdrożyć jako usługę w obszarze '{area}', etap '{innovation.Stage}', " +
+               $"z potrzeby: {request.Needs ?? "zdiagnozowanej lokalnie"}.";
+    }
+
+    private static string BuildRationale(InnovationResponse innovation, MiddlemanRequest request)
+    {
+        var institution = request.InstitutionProfile?.Type ?? "instytucja";
+
+        return $"Innowacja na etapie '{innovation.Stage}' odpowiada profilowi '{institution}' i obszarowi " +
+               $"'{request.InstitutionProfile?.Area ?? innovation.ChallengeId}', dlatego nadaje się do " +
+               "przekształcenia w powtarzalną usługę społeczną.";
+    }
+
+    private static IReadOnlyList<string> BuildResources(InnovationResponse innovation)
+    {
+        var resources = new List<string>
+        {
+            "Koordynator usługi i zespół realizacyjny",
+            "Budżet na pilotaż oraz pomiar efektów",
+        };
+
+        if (!string.IsNullOrWhiteSpace(innovation.Cost))
+        {
+            resources.Add($"Szacowany koszt: {innovation.Cost}");
+        }
+
+        resources.Add("Partnerzy lokalni (NGO/JST/firma) do wdrożenia");
+
+        return resources;
+    }
+}

backend/Infrastructure/DependencyInjection.cs

@@ -85,6 +85,12 @@ public static class DependencyInjection
         services.AddSingleton<IGrantCallService, GrantCallService>();
         services.AddSingleton<IApplicationService, ApplicationService>();
         services.AddSingleton<IIdeaAssistant, IdeaAssistant>();
+        services.AddSingleton<INotificationService, NotificationService>();
+        services.AddSingleton<IThreadService, ThreadService>();
+        services.AddSingleton<ITestFeedbackService, TestFeedbackService>();
+        services.AddSingleton<IAdminService, AdminService>();
+        services.AddSingleton<IMiddlemanService, MiddlemanAssistant>();
+        services.AddSingleton<IPartnershipService, PartnershipService>();
 
         return services;
     }

backend/Infrastructure/Persistence/AdminService.cs

@@ -0,0 +1,96 @@
+using SurrealDb.Net;
+using TarninaHub.Application.Abstractions;
+using TarninaHub.Application.Dtos;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+public sealed class AdminService : IAdminService
+{
+    private const int MaxSubmissions = 200;
+
+    private readonly ISurrealDbClient _client;
+    private readonly ISubmissionService _submissions;
+    private readonly IKnowledgeItemService _knowledgeItems;
+
+    public AdminService(
+        ISurrealDbClient client,
+        ISubmissionService submissions,
+        IKnowledgeItemService knowledgeItems)
+    {
+        _client = client;
+        _submissions = submissions;
+        _knowledgeItems = knowledgeItems;
+    }
+
+    public async Task<IReadOnlyList<SubmissionResponse>> ListSubmissionsAsync(
+        string? status,
+        string? challengeId,
+        CancellationToken cancellationToken)
+    {
+        var page = await _submissions.ListAsync(
+            viewerId: string.Empty,
+            isStaff: true,
+            status,
+            page: 1,
+            pageSize: MaxSubmissions,
+            cancellationToken);
+
+        return string.IsNullOrWhiteSpace(challengeId)
+            ? page.Items
+            : page.Items.Where(item => item.ChallengeId == challengeId).ToList();
+    }
+
+    public async Task<KnowledgeItemResponse?> VerifyKnowledgeItemAsync(
+        string knowledgeItemId,
+        VerifyKnowledgeItemRequest request,
+        CancellationToken cancellationToken)
+    {
+        var (table, id) = SurrealRecordId.Split(knowledgeItemId);
+
+        var response = await _client.RawQuery(
+            "UPDATE type::record($table, $id) SET published = $published, updated_at = time::now();",
+            new Dictionary<string, object?>
+            {
+                ["table"] = table,
+                ["id"] = id,
+                ["published"] = request.Verified,
+            },
+            cancellationToken);
+        response.EnsureAllOks();
+
+        return await _knowledgeItems.GetAsync(knowledgeItemId, cancellationToken);
+    }
+
+    public async Task<AdminMetricsResponse> GetMetricsAsync(CancellationToken cancellationToken)
+    {
+        var response = await _client.RawQuery(
+            "SELECT count() AS count FROM submission GROUP ALL; " +
+            "SELECT count() AS count FROM problem GROUP ALL; " +
+            "SELECT count() AS count FROM idea GROUP ALL; " +
+            "SELECT count() AS count FROM innovation GROUP ALL; " +
+            "SELECT count() AS count FROM knowledge_item GROUP ALL; " +
+            "SELECT count() AS count FROM user GROUP ALL; " +
+            "SELECT count() AS count FROM grant_call WHERE status = 'open' GROUP ALL; " +
+            "SELECT count() AS count FROM application GROUP ALL;",
+            new Dictionary<string, object?>(),
+            cancellationToken);
+        response.EnsureAllOks();
+
+        return new AdminMetricsResponse(
+            Count(response, 0),
+            Count(response, 1),
+            Count(response, 2),
+            Count(response, 3),
+            Count(response, 4),
+            Count(response, 5),
+            Count(response, 6),
+            Count(response, 7));
+    }
+
+    private static int Count(SurrealDb.Net.Models.Response.SurrealDbResponse response, int index)
+    {
+        var rows = response.GetValue<List<CountRow>>(index) ?? [];
+
+        return rows.Count > 0 ? rows[0].Count : 0;
+    }
+}

backend/Infrastructure/Persistence/ApplicationRow.cs

@@ -0,0 +1,19 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class ApplicationRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("grant_call")] public string GrantCall { get; set; } = string.Empty;
+
+    [CborProperty("idea")] public string Idea { get; set; } = string.Empty;
+
+    [CborProperty("content")] public Dictionary<string, string?> Content { get; set; } = [];
+
+    [CborProperty("status")] public string Status { get; set; } = string.Empty;
+
+    [CborProperty("created_at")] public DateTimeOffset CreatedAt { get; set; }
+}

backend/Infrastructure/Persistence/ApplicationService.cs

@@ -66,7 +66,7 @@ public sealed class ApplicationService : IApplicationService
                 ["grantId"] = grantId,
                 ["ideaTable"] = ideaTable,
                 ["ideaId"] = ideaIdPart,
-                ["content"] = ToStorageContent(request.Content),
+                ["content"] = request.Content ?? new Dictionary<string, string?>(),
             },
             cancellationToken);
         response.EnsureAllOks();
@@ -113,24 +113,7 @@ public sealed class ApplicationService : IApplicationService
         row.Id,
         row.GrantCall,
         row.Idea,
-        row.Content.ToDictionary(pair => pair.Key, pair => (object?)pair.Value),
+        row.Content,
         row.Status,
         row.CreatedAt);
-
-    private static Dictionary<string, string?> ToStorageContent(IReadOnlyDictionary<string, object?>? content)
-    {
-        var result = new Dictionary<string, string?>();
-
-        if (content is null)
-        {
-            return result;
-        }
-
-        foreach (var (key, value) in content)
-        {
-            result[key] = value?.ToString();
-        }
-
-        return result;
-    }
 }

backend/Infrastructure/Persistence/AuditLogService.cs

@@ -16,7 +16,7 @@ public sealed class AuditLogService : IAuditLogService
         string? actorId,
         string action,
         string target,
-        IReadOnlyDictionary<string, object?> context,
+        IReadOnlyDictionary<string, string?> context,
         CancellationToken cancellationToken)
     {
         var (actorTable, actorIdPart) = actorId is null

backend/Infrastructure/Persistence/ChallengeRow.cs

@@ -0,0 +1,15 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class ChallengeRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("name")] public string Name { get; set; } = string.Empty;
+
+    [CborProperty("description")] public string Description { get; set; } = string.Empty;
+
+    [CborProperty("order")] public int Order { get; set; }
+}

backend/Infrastructure/Persistence/ConsentRow.cs

@@ -0,0 +1,19 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class ConsentRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("user")] public string User { get; set; } = string.Empty;
+
+    [CborProperty("scope")] public string Scope { get; set; } = string.Empty;
+
+    [CborProperty("granted_at")] public DateTimeOffset GrantedAt { get; set; }
+
+    [CborProperty("expires_at")] public DateTimeOffset? ExpiresAt { get; set; }
+
+    [CborProperty("revoked_at")] public DateTimeOffset? RevokedAt { get; set; }
+}

backend/Infrastructure/Persistence/CountRow.cs

@@ -0,0 +1,9 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class CountRow
+{
+    [CborProperty("count")] public int Count { get; set; }
+}

backend/Infrastructure/Persistence/GrantCallRow.cs

@@ -0,0 +1,19 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class GrantCallRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("name")] public string Name { get; set; } = string.Empty;
+
+    [CborProperty("opens_at")] public DateTimeOffset OpensAt { get; set; }
+
+    [CborProperty("closes_at")] public DateTimeOffset ClosesAt { get; set; }
+
+    [CborProperty("status")] public string Status { get; set; } = string.Empty;
+
+    [CborProperty("external_id")] public string? ExternalId { get; set; }
+}

backend/Infrastructure/Persistence/GrantCallService.cs

@@ -55,6 +55,30 @@ public sealed class GrantCallService : IGrantCallService
         return rows.Count > 0 ? Map(rows[0]) : null;
     }
 
+    public async Task<GrantCallResponse?> UpdateStatusAsync(
+        string grantCallId,
+        string status,
+        CancellationToken cancellationToken)
+    {
+        var (table, id) = SurrealRecordId.Split(grantCallId);
+
+        var response = await _client.RawQuery(
+            "UPDATE type::record($table, $id) SET status = $status; " +
+            $"SELECT {SelectFields} FROM type::record($table, $id) LIMIT 1;",
+            new Dictionary<string, object?>
+            {
+                ["table"] = table,
+                ["id"] = id,
+                ["status"] = status,
+            },
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<GrantCallRow>>(1) ?? [];
+
+        return rows.Count > 0 ? Map(rows[0]) : null;
+    }
+
     private static GrantCallResponse Map(GrantCallRow row) => new(
         row.Id,
         row.Name,

backend/Infrastructure/Persistence/IdRow.cs

@@ -0,0 +1,9 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class IdRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+}

backend/Infrastructure/Persistence/IdeaCardRow.cs

@@ -0,0 +1,17 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class IdeaCardRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("idea")] public string Idea { get; set; } = string.Empty;
+
+    [CborProperty("essence")] public string Essence { get; set; } = string.Empty;
+
+    [CborProperty("audience")] public string Audience { get; set; } = string.Empty;
+
+    [CborProperty("stage")] public string Stage { get; set; } = string.Empty;
+}

backend/Infrastructure/Persistence/IdeaRow.cs

@@ -0,0 +1,19 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class IdeaRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("title")] public string Title { get; set; } = string.Empty;
+
+    [CborProperty("description")] public string Description { get; set; } = string.Empty;
+
+    [CborProperty("author")] public string Author { get; set; } = string.Empty;
+
+    [CborProperty("status")] public string Status { get; set; } = string.Empty;
+
+    [CborProperty("updated_at")] public DateTimeOffset? UpdatedAt { get; set; }
+}

backend/Infrastructure/Persistence/IdeaService.cs

@@ -93,6 +93,19 @@ public sealed class IdeaService : IIdeaService
         return result;
     }
 
+    public async Task<IReadOnlyList<string>> ListDistinctAuthorIdsAsync(CancellationToken cancellationToken)
+    {
+        var response = await _client.RawQuery(
+            "SELECT type::string(author) AS id FROM idea;",
+            new Dictionary<string, object?>(),
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<IdRow>>(0) ?? [];
+
+        return rows.Select(row => row.Id).Distinct(StringComparer.Ordinal).ToList();
+    }
+
     public async Task<IdeaResponse?> UpdateAsync(
         string ideaId,
         UpdateIdeaRequest request,

backend/Infrastructure/Persistence/InnovationRow.cs

@@ -0,0 +1,31 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class InnovationRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("title")] public string Title { get; set; } = string.Empty;
+
+    [CborProperty("summary")] public string Summary { get; set; } = string.Empty;
+
+    [CborProperty("description")] public string Description { get; set; } = string.Empty;
+
+    [CborProperty("challenge")] public string Challenge { get; set; } = string.Empty;
+
+    [CborProperty("stage")] public string Stage { get; set; } = string.Empty;
+
+    [CborProperty("cost")] public string? Cost { get; set; }
+
+    [CborProperty("contact")] public Dictionary<string, string?>? Contact { get; set; }
+
+    [CborProperty("media")] public List<Dictionary<string, string?>> Media { get; set; } = [];
+
+    [CborProperty("published")] public bool Published { get; set; }
+
+    [CborProperty("updated_at")] public DateTimeOffset? UpdatedAt { get; set; }
+
+    [CborProperty("embedding")] public List<float>? Embedding { get; set; }
+}

backend/Infrastructure/Persistence/InnovationService.cs

@@ -68,7 +68,7 @@ public sealed class InnovationService : IInnovationService
             ["challengeTable"] = challengeTable,
             ["challengeId"] = challengeId,
             ["stage"] = request.Stage,
-            ["media"] = request.Media ?? [],
+            ["media"] = ToConcreteList(request.Media),
             ["published"] = request.Published,
         };
 
@@ -112,7 +112,7 @@ public sealed class InnovationService : IInnovationService
             ["challengeTable"] = challengeTable,
             ["challengeId"] = challengeId,
             ["stage"] = request.Stage,
-            ["media"] = request.Media ?? [],
+            ["media"] = ToConcreteList(request.Media),
             ["published"] = request.Published,
         };
 
@@ -200,13 +200,13 @@ public sealed class InnovationService : IInnovationService
         List<string> assignments,
         Dictionary<string, object?> parameters,
         string field,
-        IReadOnlyDictionary<string, object?>? value,
+        IReadOnlyDictionary<string, string?>? value,
         bool clearWhenMissing = false)
     {
         if (value is not null)
         {
             assignments.Add($"{field} = $field_{field}");
-            parameters[$"field_{field}"] = value;
+            parameters[$"field_{field}"] = value.ToDictionary(pair => pair.Key, pair => pair.Value);
         }
         else if (clearWhenMissing)
         {
@@ -214,6 +214,10 @@ public sealed class InnovationService : IInnovationService
         }
     }
 
+    private static List<Dictionary<string, string?>> ToConcreteList(
+        IReadOnlyList<IReadOnlyDictionary<string, string?>>? values) =>
+        values?.Select(item => item.ToDictionary(pair => pair.Key, pair => pair.Value)).ToList() ?? [];
+
     private static InnovationResponse Map(InnovationRow row) => new(
         row.Id,
         row.Title,
@@ -222,8 +226,8 @@ public sealed class InnovationService : IInnovationService
         row.Challenge,
         row.Stage,
         row.Cost,
-        row.Contact is null ? null : row.Contact,
-        row.Media.Select(item => (IReadOnlyDictionary<string, object?>)item).ToList(),
+        row.Contact,
+        row.Media.Select(item => (IReadOnlyDictionary<string, string?>)item).ToList(),
         row.Published,
         row.UpdatedAt);
 }

backend/Infrastructure/Persistence/KnowledgeItemRow.cs

@@ -0,0 +1,23 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class KnowledgeItemRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("title")] public string Title { get; set; } = string.Empty;
+
+    [CborProperty("kind")] public string Kind { get; set; } = string.Empty;
+
+    [CborProperty("challenge")] public string? Challenge { get; set; }
+
+    [CborProperty("source_url")] public string? SourceUrl { get; set; }
+
+    [CborProperty("attachments")] public List<Dictionary<string, string?>> Attachments { get; set; } = [];
+
+    [CborProperty("published")] public bool Published { get; set; }
+
+    [CborProperty("updated_at")] public DateTimeOffset? UpdatedAt { get; set; }
+}

backend/Infrastructure/Persistence/KnowledgeItemService.cs

@@ -62,7 +62,7 @@ public sealed class KnowledgeItemService : IKnowledgeItemService
             ["id"] = id,
             ["title"] = request.Title,
             ["kind"] = request.Kind,
-            ["attachments"] = request.Attachments ?? [],
+            ["attachments"] = ToConcreteList(request.Attachments),
             ["published"] = request.Published,
         };
 
@@ -99,7 +99,7 @@ public sealed class KnowledgeItemService : IKnowledgeItemService
             ["id"] = id,
             ["title"] = request.Title,
             ["kind"] = request.Kind,
-            ["attachments"] = request.Attachments ?? [],
+            ["attachments"] = ToConcreteList(request.Attachments),
             ["published"] = request.Published,
         };
 
@@ -216,13 +216,17 @@ public sealed class KnowledgeItemService : IKnowledgeItemService
         }
     }
 
+    private static List<Dictionary<string, string?>> ToConcreteList(
+        IReadOnlyList<IReadOnlyDictionary<string, string?>>? values) =>
+        values?.Select(item => item.ToDictionary(pair => pair.Key, pair => pair.Value)).ToList() ?? [];
+
     private static KnowledgeItemResponse Map(KnowledgeItemRow row) => new(
         row.Id,
         row.Title,
         row.Kind,
         NormalizeRecordId(row.Challenge),
         row.SourceUrl,
-        row.Attachments.Select(item => (IReadOnlyDictionary<string, object?>)item).ToList(),
+        row.Attachments.Select(item => (IReadOnlyDictionary<string, string?>)item).ToList(),
         row.Published,
         row.UpdatedAt);
 

backend/Infrastructure/Persistence/MessageRow.cs

@@ -0,0 +1,17 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class MessageRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("thread")] public string Thread { get; set; } = string.Empty;
+
+    [CborProperty("author")] public string Author { get; set; } = string.Empty;
+
+    [CborProperty("body")] public string Body { get; set; } = string.Empty;
+
+    [CborProperty("created_at")] public DateTimeOffset CreatedAt { get; set; }
+}

backend/Infrastructure/Persistence/NotificationRow.cs

@@ -0,0 +1,17 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class NotificationRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("type")] public string Type { get; set; } = string.Empty;
+
+    [CborProperty("payload")] public Dictionary<string, string?> Payload { get; set; } = [];
+
+    [CborProperty("read_at")] public DateTimeOffset? ReadAt { get; set; }
+
+    [CborProperty("created_at")] public DateTimeOffset CreatedAt { get; set; }
+}

backend/Infrastructure/Persistence/NotificationService.cs

@@ -0,0 +1,115 @@
+using SurrealDb.Net;
+using TarninaHub.Application.Abstractions;
+using TarninaHub.Application.Dtos;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+public sealed class NotificationService : INotificationService
+{
+    private const string SelectFields =
+        "type::string(id) AS id, type, payload, read_at, created_at";
+
+    private static readonly string[] StaffRoles = ["operator", "manager", "admin"];
+
+    private readonly ISurrealDbClient _client;
+
+    public NotificationService(ISurrealDbClient client)
+    {
+        _client = client;
+    }
+
+    public async Task NotifyStaffAsync(
+        string type,
+        IReadOnlyDictionary<string, string?> payload,
+        CancellationToken cancellationToken)
+    {
+        var response = await _client.RawQuery(
+            "SELECT type::string(id) AS id FROM user WHERE role IN $roles;",
+            new Dictionary<string, object?> { ["roles"] = StaffRoles },
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<UserRow>>(0) ?? [];
+
+        foreach (var row in rows)
+        {
+            await NotifyUserAsync(row.Id, type, payload, cancellationToken);
+        }
+    }
+
+    public async Task NotifyUserAsync(
+        string userId,
+        string type,
+        IReadOnlyDictionary<string, string?> payload,
+        CancellationToken cancellationToken)
+    {
+        var notificationId = Guid.NewGuid().ToString("N");
+        var (table, id) = SurrealRecordId.Split(userId);
+
+        var response = await _client.RawQuery(
+            "CREATE type::record('notification', $id) SET recipient = type::record($table, $recipientId), " +
+            "type = $type, payload = $payload;",
+            new Dictionary<string, object?>
+            {
+                ["id"] = notificationId,
+                ["table"] = table,
+                ["recipientId"] = id,
+                ["type"] = type,
+                ["payload"] = payload,
+            },
+            cancellationToken);
+        response.EnsureAllOks();
+    }
+
+    public async Task<IReadOnlyList<NotificationResponse>> ListForUserAsync(
+        string userId,
+        CancellationToken cancellationToken)
+    {
+        var (table, id) = SurrealRecordId.Split(userId);
+
+        var response = await _client.RawQuery(
+            $"SELECT {SelectFields} FROM notification WHERE recipient = type::record($table, $id) " +
+            "ORDER BY created_at DESC;",
+            new Dictionary<string, object?> { ["table"] = table, ["id"] = id },
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<NotificationRow>>(0) ?? [];
+
+        return rows.Select(Map).ToList();
+    }
+
+    public async Task<NotificationResponse?> MarkReadAsync(
+        string notificationId,
+        string userId,
+        CancellationToken cancellationToken)
+    {
+        var (table, id) = SurrealRecordId.Split(notificationId);
+        var (userTable, userIdPart) = SurrealRecordId.Split(userId);
+
+        var response = await _client.RawQuery(
+            "UPDATE type::record($table, $id) SET read_at = time::now() " +
+            "WHERE recipient = type::record($userTable, $userId); " +
+            $"SELECT {SelectFields} FROM type::record($table, $id) LIMIT 1;",
+            new Dictionary<string, object?>
+            {
+                ["table"] = table,
+                ["id"] = id,
+                ["userTable"] = userTable,
+                ["userId"] = userIdPart,
+            },
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<NotificationRow>>(1) ?? [];
+
+        return rows.Count > 0 ? Map(rows[0]) : null;
+    }
+
+    private static NotificationResponse Map(NotificationRow row) => new(
+        row.Id,
+        row.Type,
+        row.Payload,
+        row.ReadAt,
+        row.CreatedAt);
+}

backend/Infrastructure/Persistence/PartnershipRow.cs

@@ -0,0 +1,17 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class PartnershipRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("initiator")] public string Initiator { get; set; } = string.Empty;
+
+    [CborProperty("subject")] public string Subject { get; set; } = string.Empty;
+
+    [CborProperty("partners")] public List<string> Partners { get; set; } = [];
+
+    [CborProperty("status")] public string Status { get; set; } = string.Empty;
+}

backend/Infrastructure/Persistence/PartnershipService.cs

@@ -0,0 +1,95 @@
+using SurrealDb.Net;
+using TarninaHub.Application.Abstractions;
+using TarninaHub.Application.Dtos;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+public sealed class PartnershipService : IPartnershipService
+{
+    private const string SelectFields =
+        "type::string(id) AS id, type::string(initiator) AS initiator, subject, " +
+        "array::map(partners, |$p| type::string($p)) AS partners, status";
+
+    private readonly ISurrealDbClient _client;
+
+    public PartnershipService(ISurrealDbClient client)
+    {
+        _client = client;
+    }
+
+    public async Task<IReadOnlyList<PartnershipResponse>> ListForUserAsync(
+        string userId,
+        bool isStaff,
+        CancellationToken cancellationToken)
+    {
+        var parameters = new Dictionary<string, object?>();
+        var where = string.Empty;
+
+        if (!isStaff)
+        {
+            var (table, id) = SurrealRecordId.Split(userId);
+            where = " WHERE initiator = type::record($table, $id)";
+            parameters["table"] = table;
+            parameters["id"] = id;
+        }
+
+        var response = await _client.RawQuery(
+            $"SELECT {SelectFields} FROM partnership{where} ORDER BY subject ASC;",
+            parameters,
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<PartnershipRow>>(0) ?? [];
+
+        return rows.Select(Map).ToList();
+    }
+
+    public async Task<PartnershipResponse> CreateAsync(
+        string initiatorId,
+        CreatePartnershipRequest request,
+        CancellationToken cancellationToken)
+    {
+        var partnershipId = Guid.NewGuid().ToString("N");
+        var (initiatorTable, initiatorIdPart) = SurrealRecordId.Split(initiatorId);
+        var partners = request.Partners ?? [];
+        var parameters = new Dictionary<string, object?>
+        {
+            ["id"] = partnershipId,
+            ["subject"] = request.Subject,
+            ["initiatorTable"] = initiatorTable,
+            ["initiatorId"] = initiatorIdPart,
+        };
+
+        var partnerExpressions = new List<string>(partners.Count);
+
+        for (var i = 0; i < partners.Count; i++)
+        {
+            var (table, id) = SurrealRecordId.Split(partners[i]);
+            parameters[$"table{i}"] = table;
+            parameters[$"id{i}"] = id;
+            partnerExpressions.Add($"type::record($table{i}, $id{i})");
+        }
+
+        var response = await _client.RawQuery(
+            "CREATE type::record('partnership', $id) SET " +
+            "initiator = type::record($initiatorTable, $initiatorId), subject = $subject, " +
+            $"partners = [{string.Join(", ", partnerExpressions)}], status = 'proposed'; " +
+            $"SELECT {SelectFields} FROM type::record('partnership', $id) LIMIT 1;",
+            parameters,
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<PartnershipRow>>(1) ?? [];
+
+        return rows.Count > 0
+            ? Map(rows[0])
+            : throw new InvalidOperationException("Partnership could not be loaded after creation.");
+    }
+
+    private static PartnershipResponse Map(PartnershipRow row) => new(
+        row.Id,
+        row.Initiator,
+        row.Subject,
+        row.Partners,
+        row.Status);
+}

backend/Infrastructure/Persistence/PasswordCheckRow.cs

@@ -0,0 +1,9 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class PasswordCheckRow
+{
+    [CborProperty("password_ok")] public bool PasswordOk { get; set; }
+}

backend/Infrastructure/Persistence/ProblemRow.cs

@@ -0,0 +1,21 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class ProblemRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("title")] public string Title { get; set; } = string.Empty;
+
+    [CborProperty("description")] public string Description { get; set; } = string.Empty;
+
+    [CborProperty("challenge")] public string Challenge { get; set; } = string.Empty;
+
+    [CborProperty("location")] public string Location { get; set; } = string.Empty;
+
+    [CborProperty("author")] public string Author { get; set; } = string.Empty;
+
+    [CborProperty("embedding")] public List<float>? Embedding { get; set; }
+}

backend/Infrastructure/Persistence/SubmissionRow.cs

@@ -0,0 +1,29 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class SubmissionRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("problem")] public string Problem { get; set; } = string.Empty;
+
+    [CborProperty("status")] public string Status { get; set; } = string.Empty;
+
+    [CborProperty("keywords")] public List<string> Keywords { get; set; } = [];
+
+    [CborProperty("created_at")] public DateTimeOffset CreatedAt { get; set; }
+
+    [CborProperty("updated_at")] public DateTimeOffset? UpdatedAt { get; set; }
+
+    [CborProperty("title")] public string Title { get; set; } = string.Empty;
+
+    [CborProperty("description")] public string Description { get; set; } = string.Empty;
+
+    [CborProperty("challenge")] public string Challenge { get; set; } = string.Empty;
+
+    [CborProperty("location")] public string Location { get; set; } = string.Empty;
+
+    [CborProperty("author")] public string Author { get; set; } = string.Empty;
+}

backend/Infrastructure/Persistence/SurrealRows.cs

@@ -1,215 +0,0 @@
-using Dahomey.Cbor.Attributes;
-
-namespace TarninaHub.Infrastructure.Persistence;
-
-internal sealed class UserRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("phone")] public string Phone { get; set; } = string.Empty;
-
-    [CborProperty("email")] public string? Email { get; set; }
-
-    [CborProperty("role")] public string Role { get; set; } = string.Empty;
-
-    [CborProperty("organization")] public string? Organization { get; set; }
-}
-
-internal sealed class PasswordCheckRow
-{
-    [CborProperty("password_ok")] public bool PasswordOk { get; set; }
-}
-
-internal sealed class ConsentRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("user")] public string User { get; set; } = string.Empty;
-
-    [CborProperty("scope")] public string Scope { get; set; } = string.Empty;
-
-    [CborProperty("granted_at")] public DateTimeOffset GrantedAt { get; set; }
-
-    [CborProperty("expires_at")] public DateTimeOffset? ExpiresAt { get; set; }
-
-    [CborProperty("revoked_at")] public DateTimeOffset? RevokedAt { get; set; }
-}
-
-internal sealed class SubmissionRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("problem")] public string Problem { get; set; } = string.Empty;
-
-    [CborProperty("status")] public string Status { get; set; } = string.Empty;
-
-    [CborProperty("keywords")] public List<string> Keywords { get; set; } = [];
-
-    [CborProperty("created_at")] public DateTimeOffset CreatedAt { get; set; }
-
-    [CborProperty("updated_at")] public DateTimeOffset? UpdatedAt { get; set; }
-
-    [CborProperty("title")] public string Title { get; set; } = string.Empty;
-
-    [CborProperty("description")] public string Description { get; set; } = string.Empty;
-
-    [CborProperty("challenge")] public string Challenge { get; set; } = string.Empty;
-
-    [CborProperty("location")] public string Location { get; set; } = string.Empty;
-
-    [CborProperty("author")] public string Author { get; set; } = string.Empty;
-}
-
-internal sealed class CountRow
-{
-    [CborProperty("count")] public int Count { get; set; }
-}
-
-internal sealed class ChallengeRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("name")] public string Name { get; set; } = string.Empty;
-
-    [CborProperty("description")] public string Description { get; set; } = string.Empty;
-
-    [CborProperty("order")] public int Order { get; set; }
-}
-
-internal sealed class KnowledgeItemRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("title")] public string Title { get; set; } = string.Empty;
-
-    [CborProperty("kind")] public string Kind { get; set; } = string.Empty;
-
-    [CborProperty("challenge")] public string? Challenge { get; set; }
-
-    [CborProperty("source_url")] public string? SourceUrl { get; set; }
-
-    [CborProperty("attachments")] public List<Dictionary<string, object?>> Attachments { get; set; } = [];
-
-    [CborProperty("published")] public bool Published { get; set; }
-
-    [CborProperty("updated_at")] public DateTimeOffset? UpdatedAt { get; set; }
-}
-
-internal sealed class InnovationRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("title")] public string Title { get; set; } = string.Empty;
-
-    [CborProperty("summary")] public string Summary { get; set; } = string.Empty;
-
-    [CborProperty("description")] public string Description { get; set; } = string.Empty;
-
-    [CborProperty("challenge")] public string Challenge { get; set; } = string.Empty;
-
-    [CborProperty("stage")] public string Stage { get; set; } = string.Empty;
-
-    [CborProperty("cost")] public string? Cost { get; set; }
-
-    [CborProperty("contact")] public Dictionary<string, object?>? Contact { get; set; }
-
-    [CborProperty("media")] public List<Dictionary<string, object?>> Media { get; set; } = [];
-
-    [CborProperty("published")] public bool Published { get; set; }
-
-    [CborProperty("updated_at")] public DateTimeOffset? UpdatedAt { get; set; }
-
-    [CborProperty("embedding")] public List<float>? Embedding { get; set; }
-}
-
-internal sealed class ProblemRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("title")] public string Title { get; set; } = string.Empty;
-
-    [CborProperty("description")] public string Description { get; set; } = string.Empty;
-
-    [CborProperty("challenge")] public string Challenge { get; set; } = string.Empty;
-
-    [CborProperty("location")] public string Location { get; set; } = string.Empty;
-
-    [CborProperty("author")] public string Author { get; set; } = string.Empty;
-
-    [CborProperty("embedding")] public List<float>? Embedding { get; set; }
-}
-
-internal sealed class TrendRow
-{
-    [CborProperty("challenge")] public string Challenge { get; set; } = string.Empty;
-
-    [CborProperty("count")] public int Count { get; set; }
-}
-
-internal sealed class TrendSubmissionRow
-{
-    [CborProperty("challenge")] public string Challenge { get; set; } = string.Empty;
-}
-
-internal sealed class IdRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-}
-
-internal sealed class IdeaRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("title")] public string Title { get; set; } = string.Empty;
-
-    [CborProperty("description")] public string Description { get; set; } = string.Empty;
-
-    [CborProperty("author")] public string Author { get; set; } = string.Empty;
-
-    [CborProperty("status")] public string Status { get; set; } = string.Empty;
-
-    [CborProperty("updated_at")] public DateTimeOffset? UpdatedAt { get; set; }
-}
-
-internal sealed class IdeaCardRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("idea")] public string Idea { get; set; } = string.Empty;
-
-    [CborProperty("essence")] public string Essence { get; set; } = string.Empty;
-
-    [CborProperty("audience")] public string Audience { get; set; } = string.Empty;
-
-    [CborProperty("stage")] public string Stage { get; set; } = string.Empty;
-}
-
-internal sealed class GrantCallRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("name")] public string Name { get; set; } = string.Empty;
-
-    [CborProperty("opens_at")] public DateTimeOffset OpensAt { get; set; }
-
-    [CborProperty("closes_at")] public DateTimeOffset ClosesAt { get; set; }
-
-    [CborProperty("status")] public string Status { get; set; } = string.Empty;
-
-    [CborProperty("external_id")] public string? ExternalId { get; set; }
-}
-
-internal sealed class ApplicationRow
-{
-    [CborProperty("id")] public string Id { get; set; } = string.Empty;
-
-    [CborProperty("grant_call")] public string GrantCall { get; set; } = string.Empty;
-
-    [CborProperty("idea")] public string Idea { get; set; } = string.Empty;
-
-    [CborProperty("content")] public Dictionary<string, string?> Content { get; set; } = [];
-
-    [CborProperty("status")] public string Status { get; set; } = string.Empty;
-
-    [CborProperty("created_at")] public DateTimeOffset CreatedAt { get; set; }
-}

backend/Infrastructure/Persistence/TestFeedbackRow.cs

@@ -0,0 +1,21 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class TestFeedbackRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("innovation")] public string Innovation { get; set; } = string.Empty;
+
+    [CborProperty("author")] public string Author { get; set; } = string.Empty;
+
+    [CborProperty("rating")] public int Rating { get; set; }
+
+    [CborProperty("comment")] public string Comment { get; set; } = string.Empty;
+
+    [CborProperty("improvements")] public string Improvements { get; set; } = string.Empty;
+
+    [CborProperty("created_at")] public DateTimeOffset CreatedAt { get; set; }
+}

backend/Infrastructure/Persistence/TestFeedbackService.cs

@@ -0,0 +1,90 @@
+using SurrealDb.Net;
+using TarninaHub.Application.Abstractions;
+using TarninaHub.Application.Dtos;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+public sealed class TestFeedbackService : ITestFeedbackService
+{
+    private const string SelectFields =
+        "type::string(id) AS id, type::string(innovation) AS innovation, type::string(author) AS author, " +
+        "rating, comment, improvements, created_at";
+
+    private readonly ISurrealDbClient _client;
+    private readonly IInnovationService _innovations;
+
+    public TestFeedbackService(ISurrealDbClient client, IInnovationService innovations)
+    {
+        _client = client;
+        _innovations = innovations;
+    }
+
+    public async Task<TestFeedbackResponse?> CreateAsync(
+        string innovationId,
+        string authorId,
+        CreateTestFeedbackRequest request,
+        CancellationToken cancellationToken)
+    {
+        var innovation = await _innovations.GetAsync(innovationId, cancellationToken);
+
+        if (innovation is null)
+        {
+            return null;
+        }
+
+        var feedbackId = Guid.NewGuid().ToString("N");
+        var (innovationTable, innovationIdPart) = SurrealRecordId.Split(innovationId);
+        var (authorTable, authorIdPart) = SurrealRecordId.Split(authorId);
+
+        var response = await _client.RawQuery(
+            "CREATE type::record('test_feedback', $id) SET " +
+            "innovation = type::record($innovationTable, $innovationId), " +
+            "author = type::record($authorTable, $authorId), rating = $rating, " +
+            "comment = $comment, improvements = $improvements; " +
+            $"SELECT {SelectFields} FROM type::record('test_feedback', $id) LIMIT 1;",
+            new Dictionary<string, object?>
+            {
+                ["id"] = feedbackId,
+                ["innovationTable"] = innovationTable,
+                ["innovationId"] = innovationIdPart,
+                ["authorTable"] = authorTable,
+                ["authorId"] = authorIdPart,
+                ["rating"] = request.Rating,
+                ["comment"] = request.Comment ?? string.Empty,
+                ["improvements"] = request.Improvements ?? string.Empty,
+            },
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<TestFeedbackRow>>(1) ?? [];
+
+        return rows.Count > 0 ? Map(rows[0]) : null;
+    }
+
+    public async Task<IReadOnlyList<TestFeedbackResponse>> ListForInnovationAsync(
+        string innovationId,
+        CancellationToken cancellationToken)
+    {
+        var (table, id) = SurrealRecordId.Split(innovationId);
+
+        var response = await _client.RawQuery(
+            $"SELECT {SelectFields} FROM test_feedback WHERE innovation = type::record($table, $id) " +
+            "ORDER BY created_at DESC;",
+            new Dictionary<string, object?> { ["table"] = table, ["id"] = id },
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<TestFeedbackRow>>(0) ?? [];
+
+        return rows.Select(Map).ToList();
+    }
+
+    private static TestFeedbackResponse Map(TestFeedbackRow row) => new(
+        row.Id,
+        row.Innovation,
+        row.Author,
+        row.Rating,
+        row.Comment,
+        row.Improvements,
+        row.CreatedAt);
+}

backend/Infrastructure/Persistence/ThreadRow.cs

@@ -0,0 +1,15 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class ThreadRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("subject")] public string Subject { get; set; } = string.Empty;
+
+    [CborProperty("participants")] public List<string> Participants { get; set; } = [];
+
+    [CborProperty("created_at")] public DateTimeOffset CreatedAt { get; set; }
+}

backend/Infrastructure/Persistence/ThreadService.cs

@@ -0,0 +1,204 @@
+using SurrealDb.Net;
+using TarninaHub.Application.Abstractions;
+using TarninaHub.Application.Dtos;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+public sealed class ThreadService : IThreadService
+{
+    private const string SelectThreadFields =
+        "type::string(id) AS id, subject, array::map(participants, |$p| type::string($p)) AS participants, created_at";
+
+    private const string SelectMessageFields =
+        "type::string(id) AS id, type::string(thread) AS thread, type::string(author) AS author, body, created_at";
+
+    private readonly ISurrealDbClient _client;
+
+    public ThreadService(ISurrealDbClient client)
+    {
+        _client = client;
+    }
+
+    public async Task<IReadOnlyList<ThreadResponse>> ListForUserAsync(
+        string userId,
+        bool isStaff,
+        CancellationToken cancellationToken)
+    {
+        var parameters = new Dictionary<string, object?>();
+        var where = string.Empty;
+
+        if (!isStaff)
+        {
+            var (table, id) = SurrealRecordId.Split(userId);
+            where = " WHERE participants CONTAINS type::record($table, $id)";
+            parameters["table"] = table;
+            parameters["id"] = id;
+        }
+
+        var response = await _client.RawQuery(
+            $"SELECT {SelectThreadFields} FROM thread{where} ORDER BY created_at DESC;",
+            parameters,
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<ThreadRow>>(0) ?? [];
+
+        return rows.Select(row => Map(row, [])).ToList();
+    }
+
+    public async Task<ThreadResponse?> GetAsync(
+        string threadId,
+        string userId,
+        bool isStaff,
+        CancellationToken cancellationToken)
+    {
+        var thread = await LoadThreadAsync(threadId, cancellationToken);
+
+        if (thread is null)
+        {
+            return null;
+        }
+
+        if (!isStaff && !thread.Participants.Contains(userId))
+        {
+            return null;
+        }
+
+        var messages = await LoadMessagesAsync(threadId, cancellationToken);
+
+        return Map(thread, messages);
+    }
+
+    public async Task<ThreadResponse> CreateAsync(
+        string creatorId,
+        CreateThreadRequest request,
+        CancellationToken cancellationToken)
+    {
+        var threadId = Guid.NewGuid().ToString("N");
+        var participants = new List<string> { creatorId };
+
+        foreach (var participant in request.Participants ?? [])
+        {
+            if (!string.IsNullOrWhiteSpace(participant) && !participants.Contains(participant))
+            {
+                participants.Add(participant);
+            }
+        }
+
+        var parameters = new Dictionary<string, object?>
+        {
+            ["id"] = threadId,
+            ["subject"] = request.Subject,
+        };
+
+        var recordExpressions = new List<string>(participants.Count);
+
+        for (var i = 0; i < participants.Count; i++)
+        {
+            var (table, id) = SurrealRecordId.Split(participants[i]);
+            parameters[$"table{i}"] = table;
+            parameters[$"id{i}"] = id;
+            recordExpressions.Add($"type::record($table{i}, $id{i})");
+        }
+
+        var response = await _client.RawQuery(
+            $"CREATE type::record('thread', $id) SET subject = $subject, " +
+            $"participants = [{string.Join(", ", recordExpressions)}]; " +
+            $"SELECT {SelectThreadFields} FROM type::record('thread', $id) LIMIT 1;",
+            parameters,
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<ThreadRow>>(1) ?? [];
+
+        return rows.Count > 0
+            ? Map(rows[0], [])
+            : throw new InvalidOperationException("Thread could not be loaded after creation.");
+    }
+
+    public async Task<MessageResponse?> AddMessageAsync(
+        string threadId,
+        string authorId,
+        bool isStaff,
+        CreateMessageRequest request,
+        CancellationToken cancellationToken)
+    {
+        var thread = await LoadThreadAsync(threadId, cancellationToken);
+
+        if (thread is null || (!isStaff && !thread.Participants.Contains(authorId)))
+        {
+            return null;
+        }
+
+        var messageId = Guid.NewGuid().ToString("N");
+        var (threadTable, threadIdPart) = SurrealRecordId.Split(threadId);
+        var (authorTable, authorIdPart) = SurrealRecordId.Split(authorId);
+
+        var response = await _client.RawQuery(
+            "CREATE type::record('message', $id) SET thread = type::record($threadTable, $threadId), " +
+            "author = type::record($authorTable, $authorId), body = $body; " +
+            $"SELECT {SelectMessageFields} FROM type::record('message', $id) LIMIT 1;",
+            new Dictionary<string, object?>
+            {
+                ["id"] = messageId,
+                ["threadTable"] = threadTable,
+                ["threadId"] = threadIdPart,
+                ["authorTable"] = authorTable,
+                ["authorId"] = authorIdPart,
+                ["body"] = request.Body,
+            },
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<MessageRow>>(1) ?? [];
+
+        return rows.Count > 0 ? MapMessage(rows[0]) : null;
+    }
+
+    private async Task<ThreadRow?> LoadThreadAsync(string threadId, CancellationToken cancellationToken)
+    {
+        var (table, id) = SurrealRecordId.Split(threadId);
+
+        var response = await _client.RawQuery(
+            $"SELECT {SelectThreadFields} FROM type::record($table, $id) LIMIT 1;",
+            new Dictionary<string, object?> { ["table"] = table, ["id"] = id },
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<ThreadRow>>(0) ?? [];
+
+        return rows.Count > 0 ? rows[0] : null;
+    }
+
+    private async Task<IReadOnlyList<MessageResponse>> LoadMessagesAsync(
+        string threadId,
+        CancellationToken cancellationToken)
+    {
+        var (table, id) = SurrealRecordId.Split(threadId);
+
+        var response = await _client.RawQuery(
+            $"SELECT {SelectMessageFields} FROM message WHERE thread = type::record($table, $id) " +
+            "ORDER BY created_at ASC;",
+            new Dictionary<string, object?> { ["table"] = table, ["id"] = id },
+            cancellationToken);
+        response.EnsureAllOks();
+
+        var rows = response.GetValue<List<MessageRow>>(0) ?? [];
+
+        return rows.Select(MapMessage).ToList();
+    }
+
+    private static ThreadResponse Map(ThreadRow row, IReadOnlyList<MessageResponse> messages) => new(
+        row.Id,
+        row.Subject,
+        row.Participants,
+        row.CreatedAt,
+        messages);
+
+    private static MessageResponse MapMessage(MessageRow row) => new(
+        row.Id,
+        row.Thread,
+        row.Author,
+        row.Body,
+        row.CreatedAt);
+}

backend/Infrastructure/Persistence/TrendRow.cs

@@ -0,0 +1,11 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class TrendRow
+{
+    [CborProperty("challenge")] public string Challenge { get; set; } = string.Empty;
+
+    [CborProperty("count")] public int Count { get; set; }
+}

backend/Infrastructure/Persistence/TrendSubmissionRow.cs

@@ -0,0 +1,9 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class TrendSubmissionRow
+{
+    [CborProperty("challenge")] public string Challenge { get; set; } = string.Empty;
+}

backend/Infrastructure/Persistence/UserRow.cs

@@ -0,0 +1,17 @@
+using Dahomey.Cbor.Attributes;
+
+namespace TarninaHub.Infrastructure.Persistence;
+
+
+internal sealed class UserRow
+{
+    [CborProperty("id")] public string Id { get; set; } = string.Empty;
+
+    [CborProperty("phone")] public string Phone { get; set; } = string.Empty;
+
+    [CborProperty("email")] public string? Email { get; set; }
+
+    [CborProperty("role")] public string Role { get; set; } = string.Empty;
+
+    [CborProperty("organization")] public string? Organization { get; set; }
+}