The no-auth 'add by link' path scrapes Spotify's embed widget, which only ever
contains ~100 tracks and can't paginate — so big public playlists got
truncated. This adds an in-house anonymous fetch that pulls the FULL list:
- core/spotify_public_api.py: reads the anonymous web-player accessToken Spotify
already embeds in its own open.spotify.com page HTML (no app credentials, and
no rotating TOTP secret for us to maintain), then paginates
/v1/playlists/{id}/tracks 100 at a time until the whole playlist is pulled.
Returns the embed scraper's exact shape. Pure helpers + injected http_get so
it's unit-testable without the network.
- core/spotify_public_scraper.fetch_spotify_public(): tries the full fetch for
playlists; on ANY failure (or for albums) falls back to scrape_spotify_embed.
Worst case == today's behaviour, so the link path can't regress.
- web_server: the link-tab endpoint and the authed flow's last-resort scrape
now both go through fetch_spotify_public.
Scoped entirely to the spotify_public_* (no-auth) path — the authenticated
playlist sync is untouched. 11 tests (token extraction, normalisation,
pagination past 100, and the embed-fallback orchestration).
Caveat: rides Spotify's undocumented page-embedded token — expected to break
when they change their page; it degrades to the embed fallback, never crashes.
Needs a live click-through to confirm the token path works end to end (can't
hit Spotify from the test env).
