First of three stages for system-playlist sample-history dedup
(Fable #415, server-side rotation per the operator's choice).
Schema (migration 0027):
- play_events.source (nullable text): which surface a play came
from. 'for_you' / 'discover' feed rotation; NULL for library /
user-playlist / radio / Subsonic.
- system_playlist_rotation_state(user_id, playlist_kind,
played_track_ids uuid[], rotation_started_at, updated_at): the
per-(user,kind) set of already-heard tracks this rotation.
Ingest:
- New RecordPlayStartedWithSource on the writer; RecordPlayStarted
is now a thin source="" wrapper so the frozen Subsonic shim is
untouched (no signature ripple).
- When source is a known system kind, the same txn appends the
track to rotation state (AppendRotationPlayed keeps the array a
set via the conflict CASE).
- /api/events play_started accepts an optional "source".
No serve-behavior change yet — Stage 2 makes shuffle prefer the
unplayed tail + resets on exhaustion; Stage 3 wires the clients to
send source and consume the rotation-aware order.
Tests: rotation appends + dedupes for a system source; source-less
play writes no rotation row. (Existing RecordPlayStarted tests are
unchanged — same wrapper signature, identical behavior at source="".)
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
ListRecentSessionTracks + UpdatePlayEventVector for the vector capture
path inside RecordPlayStarted. LikeTrack switches to :execrows so the
contextual-likes capture can detect insert vs already-exists. Existing
callers updated to ignore the count for now; later tasks consume it.
Tables and indexes per spec §5. session_vector_at_play ships nullable
so M3 doesn't need a follow-up migration. Table is named play_sessions
to avoid collision with the existing sessions (HTTP auth) table from
migration 0004.
bvandeusen