Applies rule 32's migration exception: each header still says what the
schema was, what changes and what it prevents, but task, milestone,
decision and rule ids are replaced by the practice they stood for, the
operator quotes by the decision, single-install counts are dropped, and
pointers to a deleted package and an external design doc are gone.
golang-migrate keeps no checksum, so editing applied migrations'
comments is safe.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Milestone #160 Opt 2b (mood half of the era+mood option). A fourth taste
facet alongside artists + genre tags + eras: signed weights over canonical
mood buckets (melancholic / energetic / chill / …) derived from a track's
enriched folksonomy tags (#1490).
- internal/mood: shared vocabulary — Of(tags) maps folksonomy tags to
canonical mood buckets (synonyms collapse). Imported by both the taste
builder and the scorer so a track's mood is derived identically.
- Migration 0047: taste_profile_moods table + taste_tuning.mood_scale
(DEFAULT 0.5).
- Build side (internal/taste): Config.MoodScale ([0,1] damper, mirrors
EraScale); accumulate folds each play/like's mood buckets at
base*MoodScale; persist atomic-replaces the mood rows.
- Scorer (internal/recommendation): TasteProfile gains a mood term
(own tanh scale + additive 0.12 share, so it never weakens the existing
signal when a track has no mood tags). Match now takes the candidate's
mood buckets; loaded per candidate (ListTrackTagsForTracks → mood.Of) in
the primary similarity loader only — the near-whole-library fallback
pool passes nil (mood → 0) to avoid a full-library tag scan.
- Tuning lab: mood_scale threaded through recsettings + admin API + web
card ("Mood weight" row) + Go/web tests.
Coverage is partial (grows with tag enrichment; richer once Last.fm is
keyed), so mood is a supplement — neutral for tracks with no mood tags.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>