Update app.json to include package name, modify index.js to use expo-router, and upgrade dependencies in package.json for improved compatibility and features.

Author: sunnylqm

Example/expoUsePushy/app.json

@@ -20,7 +20,8 @@
       "adaptiveIcon": {
         "foregroundImage": "./assets/adaptive-icon.png",
         "backgroundColor": "#ffffff"
-      }
+      },
+      "package": "com.anonymous.expoUsePushy"
     },
     "web": {
       "favicon": "./assets/favicon.png"