Fix: Radio sidebar close + topbar layout consistency

1. FAB button (favorites star) now hidden when any panel is open.
   Previously the FAB (z-index:20) covered the panel close button
   (z-index:15), making it impossible to close the station sidebar.

2. Added margin-left:auto to radio-topbar-right so theme dots
   always stay right-aligned. Previously they sat left when no
   station was playing (missing flex:1 now-playing spacer).

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

web/src/plugins/radio/RadioTab.tsx

@@ -537,14 +537,16 @@ export default function RadioTab({ data }: { data: any }) {
           )}
         </div>
 
-        {/* ── Favorites toggle ── */}
-        <button
-          className={`radio-fab ${showFavorites ? 'active' : ''}`}
-          onClick={() => { setShowFavorites(!showFavorites); if (!showFavorites) setSelectedPlace(null); }}
-          title="Favoriten"
-        >
-          {'\u2B50'}{favorites.length > 0 && <span className="radio-fab-badge">{favorites.length}</span>}
-        </button>
+        {/* ── Favorites toggle (hidden when any panel is open) ── */}
+        {!selectedPlace && !showFavorites && (
+          <button
+            className="radio-fab"
+            onClick={() => { setShowFavorites(true); setSelectedPlace(null); }}
+            title="Favoriten"
+          >
+            {'\u2B50'}{favorites.length > 0 && <span className="radio-fab-badge">{favorites.length}</span>}
+          </button>
+        )}
 
         {/* ── Side Panel: Favorites ── */}
         {showFavorites && (