feat(tracklist): play count, last played, BPM columns + Song Info rows (#730)

* feat(tracklist): play count, last played, and BPM columns (#516)

Adds three opt-in columns to Album / Playlist / Favorites tracklists,
plus the same fields in the Song Info modal. Picks up Navidrome's
existing `playCount` / `played` / `bpm` from the Subsonic response — no
new API calls.

- `SubsonicSong` gains `playCount`, `played`, `bpm` (already populated
  by Navidrome's Subsonic API, just unmapped in the TS model).
- `albumTrackListHelpers.COLUMNS`, `PL_COLUMNS` (PlaylistDetail), and
  `FAV_COLUMNS` (Favorites) get the three new entries. Genre also added
  to the playlist column set for parity with the other two lists.
- Render uses `.track-duration` (12px tabular, centered, muted) for the
  numeric stats and `.track-genre` (11px text, muted) for the relative
  last-played timestamp via the existing `formatLastSeen` helper.
- Sort logic extended in `playlistDisplayedSongs`,
  `useAlbumDetailSort`, and `useFavoritesSongFiltering` for the three
  new keys.
- `SongInfoModal` gets matching rows (BPM / Play count / Last played).
- `useTracklistColumns.gridTemplate` / `gridMinWidth` fall back to the
  ColDef's `defaultWidth` when a visible column has no saved width
  (newly added column on an old prefs blob would otherwise emit
  `undefinedpx` and collapse the row layout until reset-to-defaults).
- BPM cells skip the rendering when Navidrome returns 0 (default for
  untagged files) — show `—` instead of `0`.
- i18n: `albumDetail.trackPlayCount / trackLastPlayed / trackBpm` and
  `songInfo.playCount / lastPlayed / bpm` in all 9 locales.

Suggested by jbigginswyl (#516).

* docs(changelog): tracklist Plays / Last played / BPM columns (#730)

src/utils/useTracklistColumns.ts

@@ -71,7 +71,14 @@ export function useTracklistColumns(columns: readonly ColDef[], storageKey: stri
   const gridTemplate = useMemo(
     () =>
       visibleCols
-        .map(c => (c.flex ? `minmax(${c.minWidth}px, 1fr)` : `${colWidths[c.key]}px`))
+        .map(c => {
+          if (c.flex) return `minmax(${c.minWidth}px, 1fr)`;
+          // Defensive fallback: a column added since the last persist would have
+          // no saved width, leaving the grid template with `undefinedpx` and
+          // collapsing the row visually until the user resets defaults.
+          const w = colWidths[c.key];
+          return `${typeof w === 'number' && w > 0 ? w : c.defaultWidth}px`;
+        })
         .join(' '),
     [visibleCols, colWidths],
   );
@@ -83,7 +90,11 @@ export function useTracklistColumns(columns: readonly ColDef[], storageKey: stri
     const gapPx = 12; // --space-3
     const boxPaddingH = 24; // var(--space-3) * 2
     const colSum = visibleCols.reduce<number>(
-      (s, c) => s + (c.flex ? c.minWidth : colWidths[c.key]),
+      (s, c) => {
+        if (c.flex) return s + c.minWidth;
+        const w = colWidths[c.key];
+        return s + (typeof w === 'number' && w > 0 ? w : c.defaultWidth);
+      },
       0,
     );
     const gaps = Math.max(0, visibleCols.length - 1) * gapPx;