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/api/v1/admin/test_sound_endpoints.py

@@ -306,7 +306,8 @@ class TestAdminSoundEndpoints:
 
     @pytest.mark.asyncio
     async def test_normalize_all_sounds_unauthenticated(
-        self, client: AsyncClient,
+        self,
+        client: AsyncClient,
     ) -> None:
         """Test normalizing sounds without authentication."""
         response = await client.post("/api/v1/admin/sounds/normalize/all")