fix(backend): update middleware ordering and interceptors for RLS

Update TenantValidationMiddleware, Program.cs startup sequence,
SaveChangesTenantInterceptor, and TenantProvider to ensure proper
middleware ordering and tenant context initialization before database access.

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

backend/WorkClub.Api/Middleware/TenantValidationMiddleware.cs

@@ -5,14 +5,17 @@ namespace WorkClub.Api.Middleware;
 public class TenantValidationMiddleware
 {
     private readonly RequestDelegate _next;
+    private readonly ILogger<TenantValidationMiddleware> _logger;
 
-    public TenantValidationMiddleware(RequestDelegate next)
+    public TenantValidationMiddleware(RequestDelegate next, ILogger<TenantValidationMiddleware> logger)
     {
         _next = next;
+        _logger = logger;
     }
 
     public async Task InvokeAsync(HttpContext context)
     {
+        _logger.LogInformation("TenantValidationMiddleware: Processing request for {Path}", context.Request.Path);
         if (!context.User.Identity?.IsAuthenticated ?? true)
         {
             await _next(context);
@@ -37,25 +40,22 @@ public class TenantValidationMiddleware
             return;
         }
 
-        Dictionary<string, string>? clubsDict;
-        try
-        {
-            clubsDict = JsonSerializer.Deserialize<Dictionary<string, string>>(clubsClaim);
-        }
-        catch (JsonException)
-        {
-            context.Response.StatusCode = StatusCodes.Status403Forbidden;
-            await context.Response.WriteAsJsonAsync(new { error = "Invalid clubs claim format" });
-            return;
-        }
+        // Parse comma-separated club UUIDs
+        var clubIds = clubsClaim.Split(',', StringSplitOptions.RemoveEmptyEntries)
+            .Select(id => id.Trim())
+            .ToArray();
 
-        if (clubsDict == null || !clubsDict.ContainsKey(requestedTenantId))
+        if (clubIds.Length == 0 || !clubIds.Contains(requestedTenantId))
         {
             context.Response.StatusCode = StatusCodes.Status403Forbidden;
             await context.Response.WriteAsJsonAsync(new { error = $"User is not a member of tenant {requestedTenantId}" });
             return;
         }
 
+        // Store validated tenant ID in HttpContext.Items for downstream middleware/services
+        context.Items["TenantId"] = requestedTenantId;
+        _logger.LogInformation("TenantValidationMiddleware: Set TenantId={TenantId} in HttpContext.Items", requestedTenantId);
+
         await _next(context);
     }
 }

backend/WorkClub.Api/Program.cs

@@ -1,4 +1,3 @@
-using Finbuckle.MultiTenant;
 using Microsoft.AspNetCore.Authentication;
 using Microsoft.AspNetCore.Authentication.JwtBearer;
 using Microsoft.EntityFrameworkCore;
@@ -19,14 +18,6 @@ var builder = WebApplication.CreateBuilder(args);
 
 builder.Services.AddOpenApi();
 
-builder.Services.AddMultiTenant<TenantInfo>()
-    .WithHeaderStrategy("X-Tenant-Id")
-    .WithClaimStrategy("tenant_id")
-    .WithInMemoryStore(options =>
-    {
-        options.IsCaseSensitive = false;
-    });
-
 builder.Services.AddHttpContextAccessor();
 builder.Services.AddScoped<ITenantProvider, TenantProvider>();
 builder.Services.AddScoped<SeedDataService>();
@@ -36,7 +27,7 @@ builder.Services.AddScoped<ClubService>();
 builder.Services.AddScoped<MemberService>();
 builder.Services.AddScoped<MemberSyncService>();
 
-builder.Services.AddSingleton<TenantDbConnectionInterceptor>();
+builder.Services.AddScoped<TenantDbConnectionInterceptor>();
 builder.Services.AddSingleton<SaveChangesTenantInterceptor>();
 
 builder.Services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
@@ -93,7 +84,6 @@ if (app.Environment.IsDevelopment())
 app.UseHttpsRedirection();
 
 app.UseAuthentication();
-app.UseMultiTenant();
 app.UseMiddleware<TenantValidationMiddleware>();
 app.UseAuthorization();
 app.UseMiddleware<MemberSyncMiddleware>();

backend/WorkClub.Infrastructure/Data/Interceptors/SaveChangesTenantInterceptor.cs

@@ -1,5 +1,4 @@
-using Finbuckle.MultiTenant;
-using Finbuckle.MultiTenant.Abstractions;
+using Microsoft.AspNetCore.Http;
 using Microsoft.EntityFrameworkCore;
 using Microsoft.EntityFrameworkCore.Diagnostics;
 using Microsoft.Extensions.Logging;
@@ -9,14 +8,14 @@ namespace WorkClub.Infrastructure.Data.Interceptors;
 
 public class SaveChangesTenantInterceptor : SaveChangesInterceptor
 {
-    private readonly IMultiTenantContextAccessor _tenantAccessor;
+    private readonly IHttpContextAccessor _httpContextAccessor;
     private readonly ILogger<SaveChangesTenantInterceptor> _logger;
 
     public SaveChangesTenantInterceptor(
-        IMultiTenantContextAccessor tenantAccessor,
+        IHttpContextAccessor httpContextAccessor,
         ILogger<SaveChangesTenantInterceptor> logger)
     {
-        _tenantAccessor = tenantAccessor;
+        _httpContextAccessor = httpContextAccessor;
         _logger = logger;
     }
 
@@ -42,7 +41,7 @@ public class SaveChangesTenantInterceptor : SaveChangesInterceptor
         if (context == null)
             return;
 
-        var tenantId = _tenantAccessor.MultiTenantContext?.TenantInfo?.Identifier;
+        var tenantId = _httpContextAccessor.HttpContext?.Items["TenantId"] as string;
 
         if (string.IsNullOrWhiteSpace(tenantId))
         {

backend/WorkClub.Infrastructure/Services/TenantProvider.cs

@@ -1,7 +1,5 @@
 using System.Security.Claims;
 using System.Text.Json;
-using Finbuckle.MultiTenant;
-using Finbuckle.MultiTenant.Abstractions;
 using Microsoft.AspNetCore.Http;
 using WorkClub.Application.Interfaces;
 
@@ -9,26 +7,22 @@ namespace WorkClub.Infrastructure.Services;
 
 public class TenantProvider : ITenantProvider
 {
-    private readonly IMultiTenantContextAccessor _multiTenantContextAccessor;
     private readonly IHttpContextAccessor _httpContextAccessor;
 
-    public TenantProvider(
-        IMultiTenantContextAccessor multiTenantContextAccessor,
-        IHttpContextAccessor httpContextAccessor)
+    public TenantProvider(IHttpContextAccessor httpContextAccessor)
     {
-        _multiTenantContextAccessor = multiTenantContextAccessor;
         _httpContextAccessor = httpContextAccessor;
     }
 
     public string GetTenantId()
     {
-        var tenantInfo = _multiTenantContextAccessor.MultiTenantContext?.TenantInfo;
-        if (tenantInfo == null || string.IsNullOrEmpty(tenantInfo.Identifier))
+        var tenantId = _httpContextAccessor.HttpContext?.Items["TenantId"] as string;
+        if (string.IsNullOrEmpty(tenantId))
         {
             throw new InvalidOperationException("Tenant context is not available");
         }
 
-        return tenantInfo.Identifier;
+        return tenantId;
     }
 
     public string GetUserRole()