fix(force-recharge): 补充强充配置缺失的接口和数据库字段

- 订单管理：增加 payment_method 字段支持，合并代购订单逻辑
- 套餐系列分配：增加强充配置字段（enable_force_recharge、force_recharge_amount、force_recharge_trigger_type）
- 数据库迁移：添加 force_recharge_trigger_type 字段
- 测试：更新订单服务测试用例
- OpenSpec：归档 fix-force-recharge-missing-interfaces 变更

internal/model/shop_series_allocation.go

@@ -25,8 +25,9 @@ type ShopSeriesAllocation struct {
 	OneTimeCommissionValue     int64  `gorm:"column:one_time_commission_value;type:bigint;default:0;comment:佣金金额(分)或比例(千分比)" json:"one_time_commission_value"`
 
 	// 强充配置
-	EnableForceRecharge bool  `gorm:"column:enable_force_recharge;type:boolean;default:false;comment:是否启用强充(累计充值时可选)" json:"enable_force_recharge"`
-	ForceRechargeAmount int64 `gorm:"column:force_recharge_amount;type:bigint;default:0;comment:强充金额(分,0表示使用阈值金额)" json:"force_recharge_amount"`
+	EnableForceRecharge      bool  `gorm:"column:enable_force_recharge;type:boolean;default:false;comment:是否启用强充(累计充值时可选)" json:"enable_force_recharge"`
+	ForceRechargeAmount      int64 `gorm:"column:force_recharge_amount;type:bigint;default:0;comment:强充金额(分,0表示使用阈值金额)" json:"force_recharge_amount"`
+	ForceRechargeTriggerType int   `gorm:"column:force_recharge_trigger_type;type:int;default:2;comment:强充触发类型(1:单次充值, 2:累计充值)" json:"force_recharge_trigger_type"`
 
 	Status int `gorm:"column:status;type:int;default:1;not null;comment:状态 1-启用 2-禁用" json:"status"`
 }