feat: 添加任务状态级联触发器，优化支付和做同款功能

主要更新:
- 添加 MySQL 触发器实现 task_status 表到其他表的状态级联
- 移除控制器中的多表状态检查代码
- 完善做同款功能，支持参数传递
- 支付宝 USD 转 CNY 汇率转换
- 修复状态枚举映射问题

注意: 触发器仅在 task_status 更新时触发，部分代码仍直接更新业务表

demo/frontend/src/router/index.js

@@ -31,6 +31,8 @@ const TaskStatusPage = () => import('@/views/TaskStatusPage.vue')
 const TermsOfService = () => import('@/views/TermsOfService.vue')
 const UserAgreement = () => import('@/views/UserAgreement.vue')
 const PrivacyPolicy = () => import('@/views/PrivacyPolicy.vue')
+const ChangePassword = () => import('@/views/ChangePassword.vue')
+const SetPassword = () => import('@/views/SetPassword.vue')
 
 const routes = [
   {
@@ -212,6 +214,18 @@ const routes = [
     component: PrivacyPolicy,
     meta: { title: '隐私政策' }
   },
+  {
+    path: '/change-password',
+    name: 'ChangePassword',
+    component: ChangePassword,
+    meta: { title: '修改密码', requiresAuth: true }
+  },
+  {
+    path: '/set-password',
+    name: 'SetPassword',
+    component: SetPassword,
+    meta: { title: '设置密码', requiresAuth: true }
+  },
 ]
 
 const router = createRouter({