[Flutter] firebase 사용준비

https://firebase.flutter.dev/docs/overview/

FlutterFire Overview | FlutterFire

 

void main() async {
  WidgetsFlutterBinding.ensureInitialized(); // main 함수에서 async 사용하기 위함
  await Firebase.initializeApp(); // firebase 앱 시작
  runApp(const MyApp());
}

cd ios && arch -x86_64 pod install && cd ..