Genre explorer and deep dive modal now combine data from all available
metadata sources (iTunes + Deezer always, Spotify when authenticated).
Artists are deduplicated by name across sources, preferring entries
with images. Source dots (green/red/purple) indicate data origin.
Deezer genre support:
- Extract genre_id from Deezer album search responses via ID-to-name
mapping table (26 Deezer genre categories)
- Extract full genre names from Deezer get_album responses
- One-time backfill updates existing cached albums from stored raw_json
- Propagate album genres to Deezer artist entities
Cross-source album routing:
- /api/discover/album endpoint uses source-specific client (iTunes or
Deezer) based on the item's source, not just the active fallback
- Spotify path falls back to active fallback when album not found
- Track clicks use album_id directly instead of name-based resolution
- resolve-cache-album adds partial match and live search fallback
Other fixes:
- Genre explorer positioned at top of Discover page (below hero)
- Genre explorer results cached 24hr in-memory for fast reload
- Related genres computed from all albums by matched artists
- Artist clicks open Artists page with discography (not library detail)
- Discovery pool genre queries restored to source-filtered (Browse by
Genre tabs stay source-isolated as designed)