Stage 5 of the ABS-compat port. Adds:
- GET /abs/api/me (and /api/me)
- GET /abs/api/libraries (and /api/libraries)
- GET /abs/api/libraries/{id}
- GET /abs/api/libraries/{id}/items
- GET /abs/api/items/{id}
- GET /abs/api/items/{id}/similar
- GET /abs/api/me/items-in-progress (Continue Listening)
- Stub 200 endpoints for authors, series, search, personalized
Extends MediaStore interface: ListAudiobookLibraries and
LibraryID-filtered ListAudiobooks. Adds AudiobookLibrary struct.
Also ports collapse.go (CollapseBySeries) from the plugin — identical
logic, needed for collapseseries=1 query param support.
Author/series detail and filter-data population stubbed (empty lists);
ABS clients fall back to flat item browse when those endpoints return
empty rather than crashing.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
