feat(apps): integrate auth cubits with register and login screens

apps/lib/features/auth/ui/screens/register_screen.dart

@@ -1,26 +1,62 @@
 import 'package:flutter/material.dart';
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:formz/formz.dart';
 import 'package:go_router/go_router.dart';
 import '../../../../core/theme/design_tokens.dart';
 import '../../../../shared/widgets/app_button.dart';
+import '../../../../shared/widgets/warning_banner.dart';
+import '../../presentation/cubits/register_cubit.dart';
+import '../../data/auth_repository.dart';
 
-class RegisterScreen extends StatefulWidget {
+class RegisterScreen extends StatelessWidget {
   const RegisterScreen({super.key});
 
   @override
-  State<RegisterScreen> createState() => _RegisterScreenState();
+  Widget build(BuildContext context) {
+    return BlocProvider(
+      create: (context) => RegisterCubit(context.read<AuthRepository>()),
+      child: const RegisterView(),
+    );
+  }
 }
 
-class _RegisterScreenState extends State<RegisterScreen> {
+class RegisterView extends StatefulWidget {
+  const RegisterView({super.key});
+
+  @override
+  State<RegisterView> createState() => _RegisterViewState();
+}
+
+class _RegisterViewState extends State<RegisterView> {
   final _nicknameController = TextEditingController();
   final _emailController = TextEditingController();
+  final _passwordController = TextEditingController();
+  bool _obscureText = true;
 
   @override
   void dispose() {
     _nicknameController.dispose();
     _emailController.dispose();
+    _passwordController.dispose();
     super.dispose();
   }
 
+  Future<void> _handleNext() async {
+    final cubit = context.read<RegisterCubit>();
+    cubit.usernameChanged(_nicknameController.text);
+    cubit.emailChanged(_emailController.text);
+    cubit.passwordChanged(_passwordController.text);
+
+    if (!cubit.state.isStep1Valid) {
+      return;
+    }
+
+    final success = await cubit.submitStep1();
+    if (success && mounted) {
+      context.push('/register/step2', extra: cubit);
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     return Scaffold(
@@ -93,23 +129,39 @@ class _RegisterScreenState extends State<RegisterScreen> {
   }
 
   Widget _buildFormContainer() {
-    return SizedBox(
-      width: 327,
-      child: Column(
-        crossAxisAlignment: CrossAxisAlignment.stretch,
-        children: [
-          _buildInput('昵称', '请输入昵称', _nicknameController),
-          const SizedBox(height: 12),
-          _buildInput('邮箱', '请输入邮箱', _emailController),
-          const SizedBox(height: 12),
-          _buildStepIndicator(),
-          const SizedBox(height: 12),
-          AppButton(
-            text: '下一步',
-            onPressed: () => context.push('/register/step2'),
+    return BlocBuilder<RegisterCubit, RegisterState>(
+      builder: (context, state) {
+        return SizedBox(
+          width: 327,
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.stretch,
+            children: [
+              _buildInput('昵称', '请输入昵称', _nicknameController),
+              const SizedBox(height: 12),
+              _buildInput('邮箱', '请输入邮箱', _emailController),
+              const SizedBox(height: 12),
+              _buildPasswordInput(),
+              const SizedBox(height: 12),
+              _buildStepIndicator(),
+              if (state.errorMessage != null)
+                Padding(
+                  padding: const EdgeInsets.only(top: 8),
+                  child: WarningBanner(
+                    message: state.errorMessage!,
+                    visible: true,
+                  ),
+                ),
+              const SizedBox(height: 12),
+              AppButton(
+                text: '下一步',
+                onPressed: state.status == FormzSubmissionStatus.inProgress
+                    ? null
+                    : _handleNext,
+              ),
+            ],
           ),
-        ],
-      ),
+        );
+      },
     );
   }
 
@@ -138,6 +190,42 @@ class _RegisterScreenState extends State<RegisterScreen> {
     );
   }
 
+  Widget _buildPasswordInput() {
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        const Text(
+          '密码',
+          style: TextStyle(
+            fontSize: 13,
+            fontWeight: FontWeight.w500,
+            color: Color(0xFF475569),
+          ),
+        ),
+        const SizedBox(height: 6),
+        TextField(
+          controller: _passwordController,
+          obscureText: _obscureText,
+          decoration: InputDecoration(
+            hintText: '请输入至少 6 位密码',
+            suffixIcon: IconButton(
+              icon: Icon(
+                _obscureText ? Icons.visibility_off : Icons.visibility,
+                size: 20,
+                color: AppColors.slate400,
+              ),
+              onPressed: () {
+                setState(() {
+                  _obscureText = !_obscureText;
+                });
+              },
+            ),
+          ),
+        ),
+      ],
+    );
+  }
+
   Widget _buildStepIndicator() {
     return Row(
       children: [