Android Apple 로그인을 Firebase 웹 흐름으로

app/lib/features/auth/social_providers.dart

@@ -501,25 +501,6 @@ Future<T> untilAbandoned<T>(
   });
 }
 
-/// Apple Service ID와 callback URL은 비밀값이 아니지만 환경별 값이다.
-/// 저장소에 임시 상수를 박지 않고 빌드 시 `--dart-define`으로만 받는다.
-apple.WebAuthenticationOptions? appleWebAuthenticationOptionsFromEnvironment() {
-  const clientId = String.fromEnvironment('FANUZU_APPLE_SERVICE_ID');
-  const redirect = String.fromEnvironment('FANUZU_APPLE_REDIRECT_URI');
-  if (clientId.isEmpty || redirect.isEmpty) return null;
-
-  final redirectUri = Uri.tryParse(redirect);
-  if (redirectUri == null ||
-      !redirectUri.hasScheme ||
-      !redirectUri.hasAuthority) {
-    return null;
-  }
-  return apple.WebAuthenticationOptions(
-    clientId: clientId,
-    redirectUri: redirectUri,
-  );
-}
-
 AuthAccount _toAccount(fb.User? user, SocialProvider provider) => AuthAccount(
   uid: user?.uid ?? '',
   provider: provider,