feat: player drag feedback, global search fixes, iTunes artist discovery

- Player bar: drag handle pill + live lift/peek animation when swiping up to NP
- Global search: now includes Navidrome library results alongside iTunes; fix songs not showing (filter wrapperType=track)
- iTunes artist page: hero banner with album art, top songs section
- Artist detail: iTunes global top tracks + extra albums not on server

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

styles.css

@@ -176,6 +176,8 @@ nav{flex:1;overflow-y:auto;padding:4px 10px}
 
 /* ── PLAYER ── */
 .player{position:fixed;bottom:0;left:0;right:0;height:var(--player-h);background:rgba(8,8,20,.93);backdrop-filter:blur(28px);border-top:1px solid var(--border2);display:grid;grid-template-columns:1fr auto 1fr;align-items:center;gap:0;padding:0 20px;z-index:100}
+.player-drag-handle{position:absolute;top:5px;left:50%;transform:translateX(-50%);width:32px;height:3px;border-radius:2px;background:rgba(255,255,255,.18);transition:background .2s,width .2s;pointer-events:none}
+.player.dragging .player-drag-handle{background:rgba(255,255,255,.45);width:44px}
 .player-track{min-width:0;display:flex;align-items:center;gap:10px;overflow:visible}
 .player-art{width:52px;height:52px;border-radius:50%;background:var(--surface2);flex-shrink:0;overflow:hidden;position:relative;box-shadow:0 0 0 2px var(--surface2),0 0 0 4px rgba(255,255,255,.08)}
 .player-art img{width:100%;height:100%;object-fit:cover;border-radius:50%}