build: align icons in docs (angular#33127)

Aligns the various site icons for the docs site with angular.dev.

Fixes angular#33092.

Author: crisbeto

docs/src/assets/img/android-chrome-192x192.png

@@ -0,0 +1,19 @@
+{
+  "name": "Angular Material",
+  "short_name": "Angular Material",
+  "icons": [
+    {
+      "src": "/assets/img/android-chrome-192x192.png",
+      "sizes": "192x192",
+      "type": "image/png"
+    },
+    {
+      "src": "/assets/img/android-chrome-512x512.png",
+      "sizes": "512x512",
+      "type": "image/png"
+    }
+  ],
+  "theme_color": "#FFFFFF",
+  "background_color": "#d7e3ff",
+  "display": "standalone"
+}