Fix query and API bugs: 403 for non-owners, page bounds, lifecycle filters, cover fallback, race-safe inserts, async album delete

backend/Tests/Musify.Application.Tests/TestSupport/TestDatabase.cs

@@ -1,3 +1,4 @@
+using ErrorOr;
 using Microsoft.Data.Sqlite;
 using Microsoft.EntityFrameworkCore;
 using Musify.Application.Contracts;
@@ -79,6 +80,10 @@ public sealed class TestDatabase : DbContext, IDatabase
             .HasIndex(albumTrack => new { albumTrack.AlbumId, albumTrack.TrackId })
             .IsUnique();
 
+        modelBuilder.Entity<PlayListHasTrack>()
+            .HasIndex(playListTrack => new { playListTrack.PlayListId, playListTrack.TrackId })
+            .IsUnique();
+
         modelBuilder.Entity<Mix>()
             .HasIndex(mix => new { mix.UserId, mix.Position });
 
@@ -164,6 +169,19 @@ public sealed class TestDatabase : DbContext, IDatabase
         return new SqliteDatabaseTransaction(transaction);
     }
 
+    public async Task<ErrorOr<Success>> TrySaveChangesAsync(Error onUniqueViolation, CancellationToken cancellationToken)
+    {
+        try
+        {
+            await SaveChangesAsync(cancellationToken);
+            return Result.Success;
+        }
+        catch (DbUpdateException exception) when (exception.InnerException is SqliteException { SqliteErrorCode: 19 })
+        {
+            return onUniqueViolation;
+        }
+    }
+
     public override async ValueTask DisposeAsync()
     {
         await base.DisposeAsync();