feat(backend): add JWT authentication, RBAC and consent/audit services

Add signup/signin with backend-issued JWT (Argon2 passwords in SurrealDB), role-based authorization policies, per-user data access levels, consent register and read audit log. Protect user endpoints and record sensitive reads.

backend/Infrastructure/DependencyInjection.cs

@@ -2,6 +2,7 @@ using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using SurrealDb.Net;
 using TarninaHub.Application.Abstractions;
+using TarninaHub.Infrastructure.Auth;
 using TarninaHub.Infrastructure.Persistence;
 using TarninaHub.Infrastructure.Settings;
 
@@ -14,6 +15,7 @@ public static class DependencyInjection
         IConfiguration configuration)
     {
         services.Configure<SurrealDbSettings>(configuration.GetSection("SurrealDb"));
+        services.Configure<AuthSettings>(configuration.GetSection("Auth"));
 
         var settings = configuration.GetSection("SurrealDb").Get<SurrealDbSettings>()
             ?? new SurrealDbSettings();
@@ -46,6 +48,10 @@ public static class DependencyInjection
 
         services.AddSingleton<IStorageService, StorageService>();
         services.AddSingleton<IMigrationRunner, MigrationRunner>();
+        services.AddSingleton<ITokenService, TokenService>();
+        services.AddSingleton<IUserService, UserService>();
+        services.AddSingleton<IConsentService, ConsentService>();
+        services.AddSingleton<IAuditLogService, AuditLogService>();
 
         return services;
     }