功能：接入乐玩开放平台双渠道路由，并修复渠道锁定与 Webhook 可靠性

在保持 DLC 默认零破坏的前提下，支持 priority/仅乐玩/仅 DLC 履约策略与后台 GUI 配置；同步补齐 Prepare 渠道落库、乐玩订单取消、Webhook 验签与失败重试。

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/App.tsx

@@ -12,6 +12,7 @@ import MerchantCenter from './pages/MerchantCenter'
 import MerchantRecharge from './pages/MerchantRecharge'
 import AlertSettings from './pages/AlertSettings'
 import PlatformMerchants from './pages/PlatformMerchants'
+import PlatformProducts from './pages/PlatformProducts'
 import PlatformUsers from './pages/PlatformUsers'
 import type { ReactNode } from 'react'
 function PrivateRoute({ children }: { children: ReactNode }) {
@@ -86,6 +87,14 @@ function AppRoutes() {
             </AdminRoute>
           }
         />
+        <Route
+          path="platform-products"
+          element={
+            <AdminRoute>
+              <PlatformProducts />
+            </AdminRoute>
+          }
+        />
         <Route path="platform-users" element={<AdminRoute><PlatformUsers /></AdminRoute>} />
         <Route path="open-api" element={<MerchantPermissionRoute permission="api:manage"><OpenApiDocs /></MerchantPermissionRoute>} />
         <Route