feat: 实现密码重置功能与用户搜索API，优化注册登录流程

- 新增忘记密码页面与重置密码确认流程（前端+后端）
- 修复注册验证码页登录跳转路由
- 新增用户搜索API（按邮箱查询）
- 简化infra脚本，统一为app.sh
- 补充密码重置与用户API测试覆盖
- 更新runtime文档与AGENTS配置

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

@@ -36,6 +36,7 @@ class _RegisterViewState extends State<RegisterView> {
   final _nicknameController = TextEditingController();
   final _emailController = TextEditingController();
   final _passwordController = TextEditingController();
+  final _inviteCodeController = TextEditingController();
   bool _obscureText = true;
 
   @override
@@ -43,6 +44,7 @@ class _RegisterViewState extends State<RegisterView> {
     _nicknameController.dispose();
     _emailController.dispose();
     _passwordController.dispose();
+    _inviteCodeController.dispose();
     super.dispose();
   }
 
@@ -51,6 +53,7 @@ class _RegisterViewState extends State<RegisterView> {
     cubit.usernameChanged(_nicknameController.text);
     cubit.emailChanged(_emailController.text);
     cubit.passwordChanged(_passwordController.text);
+    cubit.inviteCodeChanged(_inviteCodeController.text);
 
     if (!cubit.state.isStep1Valid || cubit.state.isSending) {
       String? errorMsg;
@@ -159,6 +162,8 @@ class _RegisterViewState extends State<RegisterView> {
               const SizedBox(height: 12),
               _buildPasswordInput(),
               const SizedBox(height: 12),
+              _buildInput('邀请码（选填）', '请输入邀请码', _inviteCodeController),
+              const SizedBox(height: 12),
               _buildStepIndicator(),
               if (state.errorMessage != null)
                 Padding(