feat: 对齐 Waffo 包年/永久结账与客户端席位 API

同步 OpsXShell 档位定价与 Waffo 商品映射，补齐 checkout/webhook/设备列表契约，便于桌面端购买与满席释放。

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

backend/router/router.go

@@ -98,13 +98,18 @@ func SetupRouter(db *gorm.DB, cfg *config.Config) *gin.Engine {
 			register(clientAPI, "POST", "/license/activate", licenseController.ActivateDevice)
 			register(clientAPI, "POST", "/license/deactivate", licenseController.Deactivate)
 			register(clientAPI, "POST", "/license/heartbeat", licenseController.Heartbeat)
+			register(clientAPI, "POST", "/license/devices", licenseController.ListDevices)
 
 			// 产品定价查询（展示用）
+			register(clientAPI, "GET", "/products/code/:code", productController.GetByCode)
 			clientAPI.GET("/products/:product_id/plans", planController.GetByProduct)
 
 			// 订单与支付（客户端购买入口 + 支付回调）
 			register(clientAPI, "POST", "/orders", orderController.CreateOrder)
+			register(clientAPI, "POST", "/checkout", orderController.Checkout)
+			register(clientAPI, "POST", "/purchase/claim", orderController.ClaimPurchase)
 			register(clientAPI, "POST", "/webhooks/payment", orderController.PaymentWebhook)
+			register(clientAPI, "POST", "/webhooks/waffo", orderController.WaffoWebhook)
 			register(clientAPI, "POST", "/purchase/check", orderController.CheckDuplicatePurchase)
 			register(clientAPI, "POST", "/purchase/status", orderController.CheckPurchaseStatus)