The ABS mobile create-playlist modal loads existing playlists
BEFORE opening the form, hitting:
GET /api/libraries/{libraryId}/playlists
and reading `data.results` (NOT `data.playlists`). It then iterates
each playlist's `items[]` to render "already in this playlist"
badges. silo's existing `/api/playlists` route emitted the wrong
envelope (`{playlists: [...]}`) and was at the wrong path; the
modal silently treated the response as empty, the user saw an
empty existing-playlist list, and depending on the device-side
UX (no "Create New" CTA when results was undefined) the create
action looked dead.
Add handleListLibraryPlaylists at `/libraries/{libraryId}/playlists`,
emit `{results: [Playlist full-shape]}` so playlist.items is
populated for the membership check. libraryId param accepted but
ignored — silo scopes playlists per (user, profile) globally.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
