53e4f5afe6
Backend: new GET /api/photos endpoint with cursor-based pagination that queries image/video files sorted by EXIF captured_at (falling back to created_at), joining file_metadata for sort dates. Frontend: dense photo grid grouped by day with lazy-loaded thumbnails, IntersectionObserver infinite scroll, multi-select with batch download/delete, and a full-screen lightbox with prev/next navigation, EXIF metadata display, and download/favorite/delete toolbar. Includes navigation wiring, CSS (with dark theme), and i18n translations for all 9 locales.