POST /api/playlists/system/discover/refresh re-runs the system
playlist build synchronously for the calling user, then returns
their newly-built Discover playlist's UUID and track count.
Used by the frontend's "Refresh" affordances (next task) on the
Discover detail page header and the home Playlists row tile kebab.
Operator's escape hatch when they want a different randomness
without waiting for tomorrow's cron tick (e.g., after pasting a
Last.fm key, after the daily cover-art enrichment expanded their
playable library, or just for the heck of it).
Authenticated user only; the authed sub-router's RequireUser
middleware handles 401. Each user refreshes only their own
Discover — no admin route, no cross-user impersonation.
Adds GetSystemPlaylistByVariantForUser sqlc query for the response
lookup. Returns playlist_id=null and track_count=0 if the build
succeeded but the user's library yielded no eligible tracks
(degenerate empty-library).
Production list-playlists handler reuses Service.List + in-memory kind
filter so other users' public playlists can surface alongside the
caller's filtered own. Comment clarifies the divergence so future
readers don't expect this query to be wired into the API path.
Adds internal/db/queries/system_playlists.sql with 12 named queries
covering active-user enumeration, per-user run tracking (claim/finish/fail),
seed-artist/track/cover selection, and playlist CRUD by kind.
Runs sqlc generate to emit dbq/system_playlists.sql.go; also updates
playlists.sql.go and models.go to reflect the new kind/system_variant/
seed_artist_id columns added in migration 0015.
Note: plan specified a.cover_path for PickTopAlbumCoverForArtistByUser
but albums uses cover_art_path — corrected in the query file.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
bvandeusen