- Update SearchMediaItems handler to use SearchService
- Add autocomplete detection for field value queries (author=value, genre=value, etc.)
- Add handleFieldValuesSearch method for dropdown population
- Add sort parameter extraction with default "title ASC"
- Remove deprecated ListMediaItemsFiltered handler
- Remove deprecated /api/media-items/filtered route registration
- Update frontend.go to use SearchMediaItemsUnified instead of ListMediaItemsFiltered
- Fix parameter passing (empty filters use Valid:true with empty values, not Valid:false)
- Add SearchQuery, IsExactSearch, SearchPattern parameters for query parsing
Handler is now a thin wrapper that extracts params and delegates to service layer.