fix(mobile): hoist RN/Expo transitive deps for Metro resolution

pnpm's default strict isolation hides @babel/runtime/helpers/* and other
transitive deps from Metro, which expects flat node_modules layout.
Each missing dep was a separate failed EAS build (metro-runtime,
@babel/runtime, ...) — added .npmrc with public-hoist-pattern entries
that catch the common RN/Expo families so we stop whack-a-moling them.
Also kept @babel/runtime as direct dep of @chat-app/mobile for safety.

apps/mobile/package.json

@@ -18,6 +18,7 @@
     "clean": "rm -rf .expo node_modules/.cache .turbo *.tsbuildinfo"
   },
   "dependencies": {
+    "@babel/runtime": "^7.29.2",
     "@chat-app/db-types": "workspace:*",
     "@chat-app/shared": "workspace:*",
     "@config-plugins/react-native-webrtc": "^10.0.0",