fix(fin): 提现拒绝补 remark 必填校验 FIN-02

- CommissionWithdrawalHandler 新增 validator 字段
- RejectWithdrawal 在 BodyParser 后补充 validator.Struct 参数验证，确保 remark 必填

internal/bootstrap/handlers.go

@@ -58,7 +58,7 @@ func initHandlers(svc *services, deps *Dependencies) *Handlers {
 		ShopRole:                    admin.NewShopRoleHandler(svc.Shop),
 		AdminAuth:                   admin.NewAuthHandler(svc.Auth, validate),
 		ShopCommission:              admin.NewShopCommissionHandler(svc.ShopCommission),
-		CommissionWithdrawal:        admin.NewCommissionWithdrawalHandler(svc.CommissionWithdrawal),
+		CommissionWithdrawal:        admin.NewCommissionWithdrawalHandler(svc.CommissionWithdrawal, validate),
 		CommissionWithdrawalSetting: admin.NewCommissionWithdrawalSettingHandler(svc.CommissionWithdrawalSetting),
 		Enterprise:                  admin.NewEnterpriseHandler(svc.Enterprise),
 		EnterpriseCard:              admin.NewEnterpriseCardHandler(svc.EnterpriseCard),