Added .env.example template.

Author: digitalnomad91

.env.example

@@ -0,0 +1,20 @@
+# Copy this file to `.env` and fill in your values
+# These are consumed by app.config.js via dotenv at build time
+
+# Firebase config (also present in google-services.json / GoogleService-Info.plist for native)
+FIREBASE_API_KEY=
+FIREBASE_AUTH_DOMAIN=
+FIREBASE_PROJECT_ID=
+FIREBASE_STORAGE_BUCKET=
+FIREBASE_MESSAGING_SENDER_ID=
+FIREBASE_APP_ID=
+
+# Google Sign-In: REQUIRED for offline access and proper sign-in on native
+# Provide the OAuth 2.0 Client ID of type "Web application" from Google Cloud console (same project as your iOS/Android clients)
+GOOGLE_WEB_CLIENT_ID=
+
+# Optional: Maps (Android)
+GOOGLE_MAPS_API_KEY=
+
+# Build metadata
+BUILD_DATE=