Spotify similarity/new-release APIs are dead for new apps (Nov 2024 + Feb 2026),
so discovery is built on ListenBrainz similar-artists (MBID-native) behind a
pluggable SimilaritySource interface. Manual review feed of similar artists +
albums; Follow/Want reuse slice-2 operations, Dismiss is permanent. Off by default.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Jonathan