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/Tracks/DeleteTrackCommandHandlerTests.cs

@@ -39,7 +39,7 @@ public sealed class DeleteTrackCommandHandlerTests : HandlerTestBase
     }
 
     [Fact]
-    public async Task Handle_NotOwner_ReturnsUnauthorized()
+    public async Task Handle_NotOwner_ReturnsForbidden()
     {
         var owner = TestEntities.User(1, "owner");
         var stranger = TestEntities.User(2, "stranger");
@@ -48,7 +48,7 @@ public sealed class DeleteTrackCommandHandlerTests : HandlerTestBase
 
         var result = await CreateHandler().Handle(new DeleteTrackCommand(stranger.Id, track.Id), TestContext.Current.CancellationToken);
 
-        Assert.Equal(ErrorType.Unauthorized, result.FirstError.Type);
+        Assert.Equal(ErrorType.Forbidden, result.FirstError.Type);
     }
 
     [Fact]

backend/Tests/Musify.Application.Tests/Tracks/GetLastTrackListenedByUserIdQueryHandlerTests.cs

@@ -1,4 +1,3 @@
-using ErrorOr;
 using Musify.Application.Tests.TestSupport;
 using Musify.Application.Tracks;
 using Xunit;
@@ -22,18 +21,18 @@ public sealed class GetLastTrackListenedByUserIdQueryHandlerTests : HandlerTestB
 
         var result = await CreateHandler().Handle(new GetLastTrackListenedByUserIdQuery(owner.Id), TestContext.Current.CancellationToken);
 
-        Assert.False(result.IsError);
-        Assert.Equal("Newer listen", result.Value.Title);
+        Assert.NotNull(result);
+        Assert.Equal("Newer listen", result.Title);
     }
 
     [Fact]
-    public async Task Handle_NoHistory_ReturnsNotFound()
+    public async Task Handle_NoHistory_ReturnsNull()
     {
         var owner = TestEntities.User();
         await SeedAsync(owner);
 
         var result = await CreateHandler().Handle(new GetLastTrackListenedByUserIdQuery(owner.Id), TestContext.Current.CancellationToken);
 
-        Assert.Equal(ErrorType.NotFound, result.FirstError.Type);
+        Assert.Null(result);
     }
 }

backend/Tests/Musify.Application.Tests/Tracks/GetTracksByUserIdQueryHandlerTests.cs

@@ -27,19 +27,4 @@ public sealed class GetTracksByUserIdQueryHandlerTests : HandlerTestBase
         var track = Assert.Single(result.Value.Items);
         Assert.Equal("Mine", track.Title);
     }
-
-    [Theory]
-    [InlineData(0, 1)]
-    [InlineData(-5, 1)]
-    public async Task Handle_NonPositivePageNumber_FallsBackToFirstPage(int requestedPageNumber, int expectedPageNumber)
-    {
-        var owner = TestEntities.User();
-        var track = TestEntities.Track(owner);
-        await SeedAsync(owner, track, new UserHasTrack { UserId = owner.Id, TrackId = track.Id });
-
-        var result = await CreateHandler().Handle(new GetTracksByUserIdQuery(owner.Id, Name: null, PageNumber: requestedPageNumber, PageSize: 10), TestContext.Current.CancellationToken);
-
-        Assert.False(result.IsError);
-        Assert.Equal(expectedPageNumber, result.Value.PageNumber);
-    }
 }