Extract SetupService class from initialization_service to handle:
- Scan data/ folder subdirectories
- Extract title and year from folder names (YYYY pattern)
- Create AnimeSeries records in database
- Resolve provider keys via search (single exact match)
Updates _scan_folders_to_database() to delegate to SetupService.run().
Adds comprehensive unit tests for SetupService.
Lukas
5c2be3f7c4