- Add loading status fields to AnimeSeries model
- Create BackgroundLoaderService for async task processing
- Update POST /api/anime/add to return 202 Accepted immediately
- Add GET /api/anime/{key}/loading-status endpoint
- Integrate background loader with startup/shutdown lifecycle
- Create database migration script for loading status fields
- Add unit tests for BackgroundLoaderService (10 tests, all passing)
- Update AnimeSeriesService.create() to accept loading status fields
Architecture follows clean separation with no code duplication:
- BackgroundLoader orchestrates, doesn't reimplement
- Reuses existing AnimeService, NFOService, WebSocket patterns
- Database-backed status survives restarts
