fix: header search overlay clipping and mobile fit

- Change overlay from position:absolute to position:fixed so it isn't
  clipped by main-content's overflow-y:auto
- Set overlay top dynamically from header.offsetHeight so it always
  anchors exactly below the sticky header
- Responsive max-height: accounts for player bar + bottom nav on mobile
- Hide logo text on ≤359px screens to keep search pill wide enough

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

src/views.js

@@ -1017,7 +1017,12 @@ export function onHeaderSearch(val) {
   if (clearBtn) clearBtn.style.display = val ? 'block' : 'none';
   clearTimeout(S._headerSearchTimer);
   if (!val.trim()) { if (overlay) overlay.style.display = 'none'; return; }
-  if (overlay) overlay.style.display = 'block';
+  if (overlay) {
+    // position:fixed — anchor top to actual header bottom so it works with any header height
+    const header = document.getElementById('mobile-header');
+    if (header) overlay.style.top = header.offsetHeight + 'px';
+    overlay.style.display = 'block';
+  }
   const el = document.getElementById('header-search-results');
   S._headerSearchTimer = setTimeout(() => doLocalSearch(val, el), 300);
 }