Frontend:
- Add media type filter (全部/影片/照片)
- Add indexed status filter (未入庫/已入庫)
- Show media type column with icons
- Fix status filter to handle indexed/unindexed correctly
- Determine media type from file extension
Backend:
- Add total_chunks field to FileItem API response
- Query chunk counts efficiently in batch with IN clause
- Frontend uses total_chunks to determine is_indexed status