feat: 实现订单支付功能模块

- 新增订单管理、支付回调、购买验证等核心服务
- 实现订单、订单项目的数据存储层和 API 接口
- 添加订单数据库迁移和 DTO 定义
- 更新 API 文档和路由配置
- 同步 3 个新规范到主规范库（订单管理、订单支付、套餐购买验证）
- 完成 OpenSpec 变更归档

Ultraworked with Sisyphus

internal/bootstrap/handlers.go

@@ -3,6 +3,7 @@ package bootstrap
 import (
 	"github.com/break/junhong_cmp_fiber/internal/handler/admin"
 	"github.com/break/junhong_cmp_fiber/internal/handler/app"
+	"github.com/break/junhong_cmp_fiber/internal/handler/callback"
 	"github.com/break/junhong_cmp_fiber/internal/handler/h5"
 	"github.com/go-playground/validator/v10"
 )
@@ -40,5 +41,8 @@ func initHandlers(svc *services, deps *Dependencies) *Handlers {
 		ShopPackageAllocation:       admin.NewShopPackageAllocationHandler(svc.ShopPackageAllocation),
 		ShopPackageBatchAllocation:  admin.NewShopPackageBatchAllocationHandler(svc.ShopPackageBatchAllocation),
 		ShopPackageBatchPricing:     admin.NewShopPackageBatchPricingHandler(svc.ShopPackageBatchPricing),
+		AdminOrder:                  admin.NewOrderHandler(svc.Order),
+		H5Order:                     h5.NewOrderHandler(svc.Order),
+		PaymentCallback:             callback.NewPaymentHandler(svc.Order),
 	}
 }