New headphones app icon set, hardened streaming and playback, download removal controls

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

manifest.webmanifest

@@ -9,7 +9,23 @@
   "background_color": "#0f0f12",
   "theme_color": "#0f0f12",
   "icons": [
-    {"src": "/icon-192.png", "sizes": "192x192", "type": "image/png"},
-    {"src": "/icon-512.png", "sizes": "512x512", "type": "image/png"}
+    {
+      "src": "/icon-192.png",
+      "sizes": "192x192",
+      "type": "image/png",
+      "purpose": "any"
+    },
+    {
+      "src": "/icon-512.png",
+      "sizes": "512x512",
+      "type": "image/png",
+      "purpose": "any"
+    },
+    {
+      "src": "/icon-maskable-512.png",
+      "sizes": "512x512",
+      "type": "image/png",
+      "purpose": "maskable"
+    }
   ]
 }