- Add TMDBID field to ExternalIDs model
- Enhance GetExternalIDs in MovieService and TVService to fetch TMDB ID via FindTMDBIdByIMDB
- Add EnrichKPWithTMDBID function to enrich unified content with TMDB IDs
- Update unified handlers to automatically enrich KP content with TMDB IDs
- Enrich search results with TMDB IDs by fetching full film data for each result
This ensures that when using source=kp, the response includes TMDB IDs in externalIds
when available through IMDB ID mapping, while preserving all original KP data.
