feat(database): shape the library like files, and shrink the catalog

Plans 013 and 014, the album page that prompted them, and the smaller
fixes they turned up. Changelog, largest first.

## The local library is shaped like files, not like MusicBrainz

`audio_files` carries its own tags and points at `albums` and
`artists`; `file_genres` is the one real many-to-many. `recordings`,
`release_group_recordings`, `artist_credit`, `artist_credit_artist`,
`recording_genres`, `release_groups` and `release_to_rg` are gone from
the local side, and with them a six-way join in every read, a
`MIN(release_group_id)` subquery in eleven queries and a
first-credited-artist subquery in nine. Measured on a real 25,966-file
library, every many-to-many that model expressed was 1:1 in the data.

- Ownership is a file. `GetFilePathsByRecordingMBIDs`,
  `LibraryMBIDIndex.CheckMBIDs`, `collectLibraryEntities` and
  `pruneStaleLocalCrossReferences` all join `audio_files`, so the 812
  orphaned recordings, 216 release groups and 260 artists that library
  carried are now structurally impossible.
- One projection: every track query selects from the `track_metadata`
  view, one row type, one mapper. Nine hand-rolled copies had drifted
  far enough to report different years on different screens.
- `library_id = 0` means every library, so each list query exists once
  instead of scoped and unscoped with a branch at every call site.
- No migration chain. `sql/schemas/` is the one description of the
  shape; `sql/migrations/`, `applyMigrations` and `schema_migrations`
  are squashed away, along with the drift between them that had sqlc
  generating against a stale schema.
- `database.InsertTestTrack` is the one test seeder; twenty test files
  had been assembling the old FK chain each in its own order.

## The catalog stores its ids as bytes

`explore_index`'s three 36-char MBID columns and its entity-type text
are 16 raw bytes and a small integer. The table and its six indexes go
780 MB to 405 MB on a real 2,052,200-row catalog, which is why a fresh
install is ~0.6 GB rather than ~1.0 GB.

- `backend/explore/mbid.go` is the only place the encoding is known;
  everything above it speaks dashed strings.
- `CHECK(length(mbid) = 16)` makes a stringly write fail at the insert
  rather than silently returning no rows, since SQLite does not coerce
  between TEXT and BLOB.
- The importer asks the artifact what encoding it carries and converts
  on the way in, so the artifact already published keeps working and no
  format bump is needed.
- `indexRowColumns`/`scanIndexRow` replace four copies of a 22-column
  list, and `TestStoredEncodingRoundTrips` sweeps every read path.

## An album page that says how much of the album is yours

- One question, asked once: is there a file. `filePaths` is filled by a
  single batched lookup when the tracklist settles, and the badge, the
  Play count, the dimmed rows and every menu item read it — replacing
  four claims of decreasing confidence that could show a green tick on
  an album whose every action did nothing.
- Play, Play 7 of 12, or no play button at all.
- `total_tracks` on `explore_index` (~2 bytes over 400,677 release
  groups) and on `audio_files` from tags that have always carried it:
  a complete MBID-matched album now makes no catalog call at all, where
  it used to spend the most expensive request the app makes.
- A merged cluster shows the running order the most releases agree on,
  and the version list marks the release you own rather than standing a
  synthetic entry in for it.
- `AlbumReleasesFailed`: a slow fetch is no longer reported as a failed
  one by a 12-second timer.
- Rows not in the library are dimmed in place (with `aria-disabled`)
  instead of the owned ones wearing a green tick and a legend.

## Caches and cover art get ceilings

- Only the three tiers of a cover are stored; the full-resolution copy
  nothing rendered was 1,134 MB of a 1.4 GB covers directory.
- One artist portrait is downloaded and the rest are remembered as
  URLs — 4.1 GB of a 5.3 GB cache was candidates no code path reads.
- `browsedArtBudget` and `httpCacheBudget` bound what an age cannot:
  the same install held art for 5,770 artists in a 1,301-artist
  library.
- `OrphanedArtistImagesJob` joined a bare MBID onto a sharded
  directory, so it deleted the rows that were the only record of the
  files it left behind. `explore.ArtistImageDir` is that layout's one
  definition now.

## The autotag queue asks whether there is work

`tagging_items` was a row per album folder, not a queue, and no query
read the `tag_status` column that held the answer. The four queue
queries ask the files, which matters most where it is least visible:
`startPrefetch` was scoring every album in a tagged library against
MusicBrainz.

## Phantom playlist tracks resolve in place

An M3U8 imported before its files leaves phantom rows; they now match
by path and fall back to position, keep their place in the playlist
when resolved, and pair best-first so two phantoms cannot claim the
same file.

## Playing a track plays the list it is in

Double-click, and Play on a single row's menu, queue the list as
displayed with `startIndex` on that row — the album page and the track
list used to queue one track and discard the album around it. A
multi-row selection still plays exactly itself.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AfVYUVExXsx1nSWrXN8mAh

backend/database/search.go

@@ -5,6 +5,8 @@ import (
 	"database/sql"
 	"fmt"
 	"strings"
+
+	"yellowjacket/backend/database/sql/sqlcgen"
 )
 
 // SearchRow holds a single result from an FTS5 or basename search.
@@ -183,203 +185,80 @@ func (d *DB) RebuildSearchIndex() error {
 	return nil
 }
 
-// SearchTrackRow holds a full track result from an FTS5 search,
-// matching all 16 columns returned by GetAllTracksWithFullMetadata.
-type SearchTrackRow struct {
-	FilePath           string
-	LengthMilliseconds int64
-	Title              string
-	ArtistName         string
-	TrackNumber        sql.NullInt64
-	DiscNumber         sql.NullInt64
-	Album              string
-	Genre              string
-	Year               int64
-	Composer           string
-	FileType           string
-	SampleRate         int64
-	BitDepth           int64
-	Channels           int64
-	Bitrate            int64
-	FileSize           int64
+// trackMetadataColumns is the column list of the track_metadata view,
+// in the order sqlc generates TrackMetadatum's fields.  The FTS
+// searches below cannot be sqlc queries (MATCH is not in its grammar),
+// so this is the one place the view's shape is written out by hand.
+const trackMetadataColumns = `
+	tm.id, tm.file_path, tm.length_milliseconds, tm.title, tm.artist_name,
+	tm.track_number, tm.disc_number, tm.album, tm.genre, tm.year,
+	tm.release_year, tm.composer, tm.file_type, tm.sample_rate,
+	tm.bit_depth, tm.channels, tm.bitrate, tm.file_size, tm.library_id,
+	tm.play_count, tm.last_played, tm.cover_art_path, tm.artist_mbid,
+	tm.release_group_mbid, tm.recording_mbid, tm.album_id, tm.artist_id`
+
+// scanTrackMetadata reads track_metadata rows into the generated row
+// type, so an FTS hit and an ordinary query produce the same Track.
+func scanTrackMetadata(rows *sql.Rows) ([]sqlcgen.TrackMetadatum, error) {
+	var out []sqlcgen.TrackMetadatum
+
+	for rows.Next() {
+		var r sqlcgen.TrackMetadatum
+
+		if err := rows.Scan(
+			&r.ID, &r.FilePath, &r.LengthMilliseconds, &r.Title, &r.ArtistName,
+			&r.TrackNumber, &r.DiscNumber, &r.Album, &r.Genre, &r.Year,
+			&r.ReleaseYear, &r.Composer, &r.FileType, &r.SampleRate,
+			&r.BitDepth, &r.Channels, &r.Bitrate, &r.FileSize, &r.LibraryID,
+			&r.PlayCount, &r.LastPlayed, &r.CoverArtPath, &r.ArtistMbid,
+			&r.ReleaseGroupMbid, &r.RecordingMbid, &r.AlbumID, &r.ArtistID,
+		); err != nil {
+			return nil, fmt.Errorf("scan track metadata: %w", err)
+		}
+
+		out = append(out, r)
+	}
+
+	if err := rows.Err(); err != nil {
+		return nil, fmt.Errorf("iterate track metadata: %w", err)
+	}
+
+	return out, nil
 }
 
-// SearchFTSTracks performs a full-text search and returns full track
-// metadata for each match.  Unlike SearchFTS (which returns only 5
-// columns), this includes all 16 fields needed for library.Track.
+// SearchFTSTracks performs a full-text search and returns whole tracks.
+//
+// A library id of 0 means every library.  There were two of these, one
+// per case, each with its own copy of a sixteen-column projection that
+// silently dropped the MBIDs and the play count - which is why the
+// caller used to pass zeros for them.
 func (d *DB) SearchFTSTracks(
-	query string, limit int,
-) ([]SearchTrackRow, error) {
+	query string, libraryID int64, limit int,
+) ([]sqlcgen.TrackMetadatum, error) {
 	query = strings.TrimSpace(query)
 	if query == "" {
 		return nil, nil
 	}
 
-	ftsQuery := buildFTSQuery(query)
-
 	// SAFETY: FTS5 MATCH syntax unsupported by sqlc. Query is parameterized; no string interpolation.
-	rows, err := d.db.QueryContext(d.Ctx, `
-		SELECT
-			tm.file_path,
-			tm.length_milliseconds,
-			tm.title,
-			tm.artist_name,
-			tm.track_number,
-			tm.disc_number,
-			tm.album,
-			tm.genre,
-			tm.year,
-			tm.composer,
-			tm.file_type,
-			tm.sample_rate,
-			tm.bit_depth,
-			tm.channels,
-			tm.bitrate,
-			tm.file_size
+	rows, err := d.reader().QueryContext(d.Ctx, `
+		SELECT`+trackMetadataColumns+`
 		FROM search_index si
 		JOIN track_metadata tm ON tm.id = si.rowid
 		WHERE search_index MATCH ?
+		  AND (? = 0 OR tm.library_id = ?)
 		ORDER BY rank
 		LIMIT ?
-	`, ftsQuery, limit)
+	`, buildFTSQuery(query), libraryID, libraryID, limit)
 	if err != nil {
-		return nil, fmt.Errorf(
-			"FTS track search failed: %w", err,
-		)
+		return nil, fmt.Errorf("FTS track search failed: %w", err)
 	}
 
 	defer func() { _ = rows.Close() }()
 
-	var results []SearchTrackRow
-
-	for rows.Next() {
-		var r SearchTrackRow
-
-		if err := rows.Scan(
-			&r.FilePath,
-			&r.LengthMilliseconds,
-			&r.Title,
-			&r.ArtistName,
-			&r.TrackNumber,
-			&r.DiscNumber,
-			&r.Album,
-			&r.Genre,
-			&r.Year,
-			&r.Composer,
-			&r.FileType,
-			&r.SampleRate,
-			&r.BitDepth,
-			&r.Channels,
-			&r.Bitrate,
-			&r.FileSize,
-		); err != nil {
-			return nil, fmt.Errorf(
-				"could not scan search track row: %w",
-				err,
-			)
-		}
-
-		results = append(results, r)
-	}
-
-	if err := rows.Err(); err != nil {
-		return nil, fmt.Errorf(
-			"search track row iteration error: %w",
-			err,
-		)
-	}
-
-	return results, nil
+	return scanTrackMetadata(rows)
 }
 
-// SearchFTSTracksByLibrary performs a full-text search scoped to a
-// specific library and returns full track metadata for each match.
-func (d *DB) SearchFTSTracksByLibrary(
-	query string, limit int, libraryID int64,
-) ([]SearchTrackRow, error) {
-	query = strings.TrimSpace(query)
-	if query == "" {
-		return nil, nil
-	}
-
-	ftsQuery := buildFTSQuery(query)
-
-	// SAFETY: FTS5 MATCH syntax unsupported by sqlc. Query is parameterized; no string interpolation.
-	rows, err := d.db.QueryContext(d.Ctx, `
-		SELECT
-			tm.file_path,
-			tm.length_milliseconds,
-			tm.title,
-			tm.artist_name,
-			tm.track_number,
-			tm.disc_number,
-			tm.album,
-			tm.genre,
-			tm.year,
-			tm.composer,
-			tm.file_type,
-			tm.sample_rate,
-			tm.bit_depth,
-			tm.channels,
-			tm.bitrate,
-			tm.file_size
-		FROM search_index si
-		JOIN track_metadata tm ON tm.id = si.rowid
-		WHERE search_index MATCH ? AND tm.library_id = ?
-		ORDER BY rank
-		LIMIT ?
-	`, ftsQuery, libraryID, limit)
-	if err != nil {
-		return nil, fmt.Errorf(
-			"FTS library track search failed: %w", err,
-		)
-	}
-
-	defer func() { _ = rows.Close() }()
-
-	var results []SearchTrackRow
-
-	for rows.Next() {
-		var r SearchTrackRow
-
-		if err := rows.Scan(
-			&r.FilePath,
-			&r.LengthMilliseconds,
-			&r.Title,
-			&r.ArtistName,
-			&r.TrackNumber,
-			&r.DiscNumber,
-			&r.Album,
-			&r.Genre,
-			&r.Year,
-			&r.Composer,
-			&r.FileType,
-			&r.SampleRate,
-			&r.BitDepth,
-			&r.Channels,
-			&r.Bitrate,
-			&r.FileSize,
-		); err != nil {
-			return nil, fmt.Errorf(
-				"could not scan library search track row: %w",
-				err,
-			)
-		}
-
-		results = append(results, r)
-	}
-
-	if err := rows.Err(); err != nil {
-		return nil, fmt.Errorf(
-			"library search track row iteration error: %w",
-			err,
-		)
-	}
-
-	return results, nil
-}
-
-// scanSearchRows reads all rows from a query result into a slice.
 func scanSearchRows(
 	rows interface {
 		Next() bool