feat: implement Labels section in Artist Network sidebar

- Add labels field to ArtistDetail type
- Extract unique labels from artist albums in convertQobuzArtist
- Update appendArtistAlbums to merge new labels
- Display labels in sidebar with click navigation to label view
- Use Tag icon from lucide-svelte

src/routes/+page.svelte

@@ -2596,6 +2596,7 @@
           onTrackGoToAlbum={handleAlbumClick}
           onTrackGoToArtist={handleArtistClick}
           onPlaylistClick={selectPlaylist}
+          onLabelClick={handleLabelClick}
           activeTrackId={currentTrack?.id ?? null}
           isPlaybackActive={isPlaying}
         />