fix: per-span hover highlight, use • as artist separator everywhere

- CSS: target #player-artist-name span:hover and #np-artist-name span:hover so only the hovered artist name highlights, not all at once
- change artist separator from / to • in song items, player bar, now playing overlay, album header

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/views.js

@@ -426,7 +426,7 @@ export async function loadAlbumDetail(album) {
   artistEl.innerHTML = albumArtistParts.map((name, i) => {
     const aid = i === 0 ? (album.artistId || '') : '';
     return `<span class="song-link" onclick="s_goArtist(event,${JSON.stringify(name)},${JSON.stringify(aid)})">${esc(name)}</span>`;
-  }).join('<span style="color:var(--text3)"> / </span>') || '';
+  }).join('<span style="color:var(--text3)"> • </span>') || '';
   const cw = document.getElementById('album-cover-wrap');
   const cv = coverUrl(album.coverArt, 300);
   cw.innerHTML = cv ? `<img src="${cv}" onerror="this.parentNode.innerHTML='<div class=\\'no-art\\'>💿</div>'">` : '<div class="no-art">💿</div>';