Refactor sound and extraction services to include user and timestamp fields

- Updated ExtractionInfo to include user_id, created_at, and updated_at fields.
- Modified ExtractionService to return user and timestamp information in extraction responses.
- Enhanced sound serialization in PlayerState to include extraction URL if available.
- Adjusted PlaylistRepository to load sound extractions when retrieving playlist sounds.
- Added tests for new fields in extraction and sound endpoints, ensuring proper response structure.
- Created new test file endpoints for sound downloads and thumbnail retrievals, including success and error cases.
- Refactored various test cases for consistency and clarity, ensuring proper mocking and assertions.

tests/services/test_socket_service.py

@@ -270,7 +270,9 @@ class TestSocketManager:
 
     @pytest.mark.asyncio
     async def test_disconnect_handler_unknown_socket(
-        self, socket_manager, mock_sio,
+        self,
+        socket_manager,
+        mock_sio,
     ) -> None:
         """Test disconnect handler with unknown socket."""
         # Access the disconnect handler directly