Phase 2 refinements: Firebase config, dev environment fixes, phase 3 requirement draft

- Integrated Firebase SDK in both Flutter apps (google-services, firebase_options)
- Fixed auth flow, API client, and pairing/status blocs for dev environment
- Added full Flutter project scaffolds (android, ios, web, etc.)
- Added phase 3 chat engine requirement document
- Added bugreport zip pattern to gitignore

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

mitra_app/lib/core/auth/auth_bloc.dart

@@ -1,5 +1,7 @@
+import 'dart:async';
 import 'package:equatable/equatable.dart';
 import 'package:firebase_auth/firebase_auth.dart';
+import 'package:flutter/foundation.dart' show kIsWeb;
 import 'package:flutter_bloc/flutter_bloc.dart';
 import '../api/api_client.dart';
 
@@ -51,6 +53,7 @@ class AuthError extends AuthState {
 class AuthBloc extends Bloc<AuthEvent, AuthState> {
   final ApiClient apiClient;
   final _auth = FirebaseAuth.instance;
+  ConfirmationResult? _webConfirmationResult;
 
   AuthBloc({required this.apiClient}) : super(AuthInitial()) {
     on<AppStarted>(_onAppStarted);
@@ -67,23 +70,50 @@ class AuthBloc extends Bloc<AuthEvent, AuthState> {
 
   Future<void> _onPhoneOtpRequested(PhoneOtpRequested event, Emitter<AuthState> emit) async {
     emit(AuthLoading());
-    await _auth.verifyPhoneNumber(
-      phoneNumber: event.phone,
-      verificationCompleted: (_) {},
-      verificationFailed: (e) => emit(AuthError('Gagal mengirim OTP. Coba lagi.')),
-      codeSent: (verificationId, _) => emit(AuthOtpSent(verificationId)),
-      codeAutoRetrievalTimeout: (_) {},
-    );
+
+    if (kIsWeb) {
+      try {
+        final confirmationResult = await _auth.signInWithPhoneNumber(event.phone);
+        _webConfirmationResult = confirmationResult;
+        emit(AuthOtpSent('web'));
+      } catch (e) {
+        emit(AuthError('Gagal mengirim OTP. Coba lagi.'));
+      }
+    } else {
+      final completer = Completer<void>();
+      await _auth.verifyPhoneNumber(
+        phoneNumber: event.phone,
+        verificationCompleted: (_) {
+          if (!completer.isCompleted) completer.complete();
+        },
+        verificationFailed: (e) {
+          emit(AuthError('Gagal mengirim OTP. Coba lagi.'));
+          if (!completer.isCompleted) completer.complete();
+        },
+        codeSent: (verificationId, _) {
+          emit(AuthOtpSent(verificationId));
+          if (!completer.isCompleted) completer.complete();
+        },
+        codeAutoRetrievalTimeout: (_) {
+          if (!completer.isCompleted) completer.complete();
+        },
+      );
+      await completer.future;
+    }
   }
 
   Future<void> _onOtpVerified(OtpVerified event, Emitter<AuthState> emit) async {
     emit(AuthLoading());
     try {
-      final credential = PhoneAuthProvider.credential(
-        verificationId: event.verificationId,
-        smsCode: event.smsCode,
-      );
-      await _auth.signInWithCredential(credential);
+      if (kIsWeb && _webConfirmationResult != null) {
+        await _webConfirmationResult!.confirm(event.smsCode);
+      } else {
+        final credential = PhoneAuthProvider.credential(
+          verificationId: event.verificationId,
+          smsCode: event.smsCode,
+        );
+        await _auth.signInWithCredential(credential);
+      }
       await _verifyAndEmit(emit);
     } catch (e) {
       emit(AuthError('OTP tidak valid. Coba lagi.'));