Updated metadata provider interfaces and implementations to return null instead of placeholder objects when data cannot be resolved. This improves error handling and reduces unnecessary object creation.
- Modified schema types to include null unions (e.g., ResolvedMovieMetadataResult)
- Changed runtime fields from minutes to seconds for consistency
- Removed placeholder builders in TMDB provider, returning null directly
- Optimized library scanner by removing redundant file counting and adding early exits for existing media
- Ensured type safety across services and providers
BREAKING CHANGE: Metadata resolution methods now return null for unresolved data, requiring consumers to handle null cases explicitly.