feat: add home and profile screens

lib/app.dart

@@ -3,16 +3,43 @@ import 'package:go_router/go_router.dart';
 import 'package:phone_login/auth/auth_state.dart';
 import 'package:phone_login/auth/phone_input_screen.dart';
 import 'package:phone_login/auth/sms_verification_screen.dart';
+import 'package:phone_login/home/home_screen.dart';
+import 'package:phone_login/profile/profile_screen.dart';
 import 'package:provider/provider.dart';
 
 final _router = GoRouter(
   routes: [
-    GoRoute(path: '/', builder: (context, state) => const PhoneInputScreen()),
+    GoRoute(path: '/', builder: (context, state) => const HomeScreen()),
+    GoRoute(
+      path: '/login',
+      builder: (context, state) => const PhoneInputScreen(),
+    ),
     GoRoute(
       path: '/sms_verify',
       builder: (context, state) => const SmsVerificationScreen(),
     ),
+    GoRoute(
+      path: '/profile',
+      builder: (context, state) => const ProfileScreen(),
+    ),
   ],
+  redirect: (BuildContext context, GoRouterState state) {
+    final authState = Provider.of<AuthState>(context, listen: false);
+    final bool loggedIn = authState.isLoggedIn;
+    final bool loggingIn =
+        state.matchedLocation == '/login' ||
+        state.matchedLocation == '/sms_verify';
+
+    if (!loggedIn && !loggingIn) {
+      return '/login';
+    }
+
+    if (loggedIn && loggingIn) {
+      return '/';
+    }
+
+    return null;
+  },
 );
 
 class App extends StatelessWidget {