feat(ideas): add idea creator, grant calls and applications

Implement the idea creator and application generator: idea status workflow, social canvas card, grant call windows with 409 when closed, and an LLM-backed idea assistant with offline fallback.

backend/Controllers/GrantCallsController.cs

@@ -0,0 +1,41 @@
+using Asp.Versioning;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using TarninaHub.Application.Abstractions;
+using TarninaHub.Application.Dtos;
+
+namespace TarninaHub.Controllers;
+
+[ApiController]
+[ApiVersion("1.0")]
+[Route("api/grant-calls")]
+[Authorize]
+public class GrantCallsController : ControllerBase
+{
+    private readonly IGrantCallService _grantCalls;
+
+    public GrantCallsController(IGrantCallService grantCalls)
+    {
+        _grantCalls = grantCalls;
+    }
+
+    [HttpGet]
+    public async Task<ActionResult<IReadOnlyList<GrantCallResponse>>> List(
+        [FromQuery] string? status,
+        CancellationToken cancellationToken)
+    {
+        var calls = await _grantCalls.ListAsync(status, cancellationToken);
+
+        return Ok(calls);
+    }
+
+    [HttpGet("{grantCallId}")]
+    public async Task<ActionResult<GrantCallResponse>> GetById(
+        string grantCallId,
+        CancellationToken cancellationToken)
+    {
+        var call = await _grantCalls.GetAsync(grantCallId, cancellationToken);
+
+        return call is null ? NotFound() : Ok(call);
+    }
+}