refactor: 移除前端 Mock API，新增共享组件，优化认证流程

- 删除 mock_api_client、mock_calendar_service、mock_history_service
- 新增 fixed_length_code_input、link_button、message_composer 共享组件
- 优化登录/注册/密码重置页面使用新组件
- 简化 injection.dart 移除 mock 分支
- 更新 env.dart 配置（BACKEND_URL 替换 API_URL）
- 后端 agentscope 工具和测试更新
- 重构 AGENTS.md 文档结构
- 新增 deploy/ 目录和 protocol 文档

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

@@ -6,6 +6,8 @@ import 'package:go_router/go_router.dart';
 import 'package:formz/formz.dart';
 import '../../../../core/theme/design_tokens.dart';
 import '../../../../shared/widgets/app_button.dart';
+import '../../../../shared/widgets/fixed_length_code_input.dart';
+import '../../../../shared/widgets/link_button.dart';
 import '../../../../shared/widgets/toast/toast.dart';
 import '../../../../shared/widgets/toast/toast_type.dart';
 import '../../presentation/cubits/register_cubit.dart';
@@ -49,22 +51,10 @@ class _RegisterVerificationViewState extends State<RegisterVerificationView> {
   Timer? _countdownTimer;
   int _countdown = 0;
   bool _firstSendCompleted = false;
-  bool _hintShown = false;
 
   @override
   void initState() {
     super.initState();
-    WidgetsBinding.instance.addPostFrameCallback((_) {
-      if (!_hintShown) {
-        _hintShown = true;
-        Toast.show(
-          context,
-          '验证码已发送，如未收到请检查垃圾邮件或确认邮箱已注册',
-          type: ToastType.info,
-          duration: const Duration(seconds: 5),
-        );
-      }
-    });
   }
 
   @override
@@ -200,6 +190,12 @@ class _RegisterVerificationViewState extends State<RegisterVerificationView> {
             !_firstSendCompleted) {
           _firstSendCompleted = true;
           _startCountdown();
+          Toast.show(
+            context,
+            '验证码已发送，如未收到请检查垃圾邮件或确认邮箱已注册',
+            type: ToastType.info,
+            duration: const Duration(seconds: 5),
+          );
         }
       },
       builder: (context, state) {
@@ -246,16 +242,28 @@ class _RegisterVerificationViewState extends State<RegisterVerificationView> {
             Expanded(
               child: SizedBox(
                 height: 40,
-                child: TextField(
+                child: FixedLengthCodeInput(
                   controller: _codeController,
+                  length: 6,
+                  semanticLabel: '邮箱验证码输入框',
                   keyboardType: TextInputType.number,
-                  decoration: const InputDecoration(
-                    hintText: '输入验证码',
-                    contentPadding: EdgeInsets.symmetric(
-                      horizontal: 12,
-                      vertical: 10,
-                    ),
-                  ),
+                  allowedCharacters: const {
+                    '0',
+                    '1',
+                    '2',
+                    '3',
+                    '4',
+                    '5',
+                    '6',
+                    '7',
+                    '8',
+                    '9',
+                  },
+                  onChanged: (value) {
+                    context.read<RegisterCubit>().verificationCodeChanged(
+                      value,
+                    );
+                  },
                 ),
               ),
             ),
@@ -268,36 +276,38 @@ class _RegisterVerificationViewState extends State<RegisterVerificationView> {
   }
 
   Widget _buildResendButton(bool canResend, RegisterState state) {
-    final bgColor = canResend ? AppColors.primary : const Color(0xFFF1F5F9);
-    final textColor = canResend ? AppColors.white : AppColors.slate400;
+    final canPress =
+        canResend && state.status != FormzSubmissionStatus.inProgress;
 
-    String text;
-    if (state.status == FormzSubmissionStatus.inProgress) {
-      text = '发送中';
-    } else if (canResend) {
-      text = '重发';
-    } else {
-      text = '${_countdown}s';
-    }
-
-    return GestureDetector(
-      onTap: canResend ? _handleResendCode : null,
-      child: Container(
-        width: 70,
-        height: 40,
-        decoration: BoxDecoration(
-          color: bgColor,
-          borderRadius: BorderRadius.circular(6),
-        ),
-        alignment: Alignment.center,
-        child: Text(
-          text,
-          style: TextStyle(
-            fontSize: 14,
-            fontWeight: FontWeight.w500,
-            color: textColor,
+    return SizedBox(
+      width: 70,
+      height: 44,
+      child: TextButton(
+        onPressed: canPress ? _handleResendCode : null,
+        style: TextButton.styleFrom(
+          backgroundColor: canResend ? AppColors.primary : AppColors.slate100,
+          foregroundColor: canResend ? AppColors.white : AppColors.slate400,
+          shape: RoundedRectangleBorder(
+            borderRadius: BorderRadius.circular(AppRadius.sm),
           ),
+          padding: EdgeInsets.zero,
         ),
+        child: state.status == FormzSubmissionStatus.inProgress
+            ? const SizedBox(
+                width: 16,
+                height: 16,
+                child: CircularProgressIndicator(
+                  strokeWidth: 2,
+                  valueColor: AlwaysStoppedAnimation<Color>(AppColors.slate400),
+                ),
+              )
+            : Text(
+                canResend ? '重发' : '${_countdown}s',
+                style: const TextStyle(
+                  fontSize: 14,
+                  fontWeight: FontWeight.w500,
+                ),
+              ),
       ),
     );
   }
@@ -329,16 +339,6 @@ class _RegisterVerificationViewState extends State<RegisterVerificationView> {
   }
 
   Widget _buildFooter() {
-    return GestureDetector(
-      onTap: () => context.go('/'),
-      child: const Text(
-        '已有账号？去登录',
-        style: TextStyle(
-          fontSize: 14,
-          fontWeight: FontWeight.w500,
-          color: AppColors.slate500,
-        ),
-      ),
-    );
+    return LinkButton(text: '已有账号？去登录', onTap: () => context.go('/'));
   }
 }