chore(mobile): remove @expo/ngrok tunneling dependency

Dropped @expo/ngrok (and its 40 platform binary packages) from apps/mobile.
It was only used by `expo start --tunnel` (public dev-server tunnel) — never
imported in app code and unrelated to token storage (that is expo-secure-store).
Removed per IT request; no functional impact on the app or auth.

apps/mobile/package.json

@@ -10,7 +10,6 @@
     "@anythingai/app": "0.1.96",
     "@expo-google-fonts/dev": "0.4.7",
     "@expo-google-fonts/inter": "0.4.2",
-    "@expo/ngrok": "4.1.3",
     "@expo/vector-icons": "15.0.3",
     "@gorhom/bottom-sheet": "5.2.6",
     "@react-native-async-storage/async-storage": "2.2.0",