fix: duplicate rows in artist "Top Songs" when a track exists twice in the library

Navidrome can hold the same track twice (downloaded as a single AND as an album track), so
getTopSongs returned two identical rows ("PIXELATED KISSES" x2). Collapse the top-songs list
by title+album for display (keeps the highest play count) on web + Android. SW ns-v59.

Note: this is a display fix — the underlying duplicate files remain a library-cleanup matter.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/views/detail.js

@@ -219,7 +219,14 @@ export async function loadArtistDetail(artist) {
 
   // ── Top Songs ──
   const ndAlbums    = _ndArtist?.album || [];
-  const topSongs    = topRes.status   === 'fulfilled' ? (topRes.value?.topSongs?.song  || []) : [];
+  // Navidrome can hold the same track twice (e.g. downloaded as a single AND as an album track),
+  // so getTopSongs returns duplicate rows ("PIXELATED KISSES" x2). Collapse by title+album for display.
+  const _rawTop     = topRes.status   === 'fulfilled' ? (topRes.value?.topSongs?.song  || []) : [];
+  const _seenTop    = new Set();
+  const topSongs    = _rawTop.filter(s => {
+    const k = `${s.title}|${s.album}`.toLowerCase().replace(/[^a-z0-9|]/g, '');
+    return _seenTop.has(k) ? false : (_seenTop.add(k), true);
+  });
   const iTracks     = iTracksRes.status === 'fulfilled' ? (iTracksRes.value || []).filter(t => t.wrapperType === 'track') : [];
   const iAlbums     = iAlbumsRes.status === 'fulfilled' ? (iAlbumsRes.value || []) : [];