fix: 修复微信/富友支付回调配置加载错误

- WechatPayCallback 移除对永远为 nil 的单例 wechatPayment 的依赖，
  改为动态按 payment_config_id 加载创建订单时所用的精确配置
- PaymentV2Service 新增 VerifyCallback()（v2 XML 验签）和 PeekOrderNo()（不验签预解析）
- FuiouPayCallback 由 GetActiveConfig 改为 GetConfigForCallback，
  通过 ParseNotify 预解析订单号后精确加载配置，防止切换配置后旧订单验签失败
- wechat_config.Service 注入 assetRechargeStore/agentRechargeStore，
  新增 GetConfigForCallback()：按订单号前缀查 payment_config_id，
  GetByIDUnscoped 加载配置（含已停用/软删除记录），找不到则回退激活配置
- 修复微信 v2 回调响应格式：从 JSON 改为 XML，避免微信持续重试

internal/service/wechat_config/service.go

@@ -31,21 +31,33 @@ type AuditServiceInterface interface {
 
 // Service 微信参数配置业务服务
 type Service struct {
-	store        *postgres.WechatConfigStore
-	orderStore   *postgres.OrderStore
-	auditService AuditServiceInterface
-	redis        *redis.Client
-	logger       *zap.Logger
+	store              *postgres.WechatConfigStore
+	orderStore         *postgres.OrderStore
+	assetRechargeStore *postgres.AssetRechargeStore
+	agentRechargeStore *postgres.AgentRechargeStore
+	auditService       AuditServiceInterface
+	redis              *redis.Client
+	logger             *zap.Logger
 }
 
 // New 创建微信参数配置服务实例
-func New(store *postgres.WechatConfigStore, orderStore *postgres.OrderStore, auditService AuditServiceInterface, rdb *redis.Client, logger *zap.Logger) *Service {
+func New(
+	store *postgres.WechatConfigStore,
+	orderStore *postgres.OrderStore,
+	assetRechargeStore *postgres.AssetRechargeStore,
+	agentRechargeStore *postgres.AgentRechargeStore,
+	auditService AuditServiceInterface,
+	rdb *redis.Client,
+	logger *zap.Logger,
+) *Service {
 	return &Service{
-		store:        store,
-		orderStore:   orderStore,
-		auditService: auditService,
-		redis:        rdb,
-		logger:       logger,
+		store:              store,
+		orderStore:         orderStore,
+		assetRechargeStore: assetRechargeStore,
+		agentRechargeStore: agentRechargeStore,
+		auditService:       auditService,
+		redis:              rdb,
+		logger:             logger,
 	}
 }
 
@@ -471,3 +483,58 @@ func (s *Service) mergeSensitiveField(target *string, newVal *string) {
 		*target = *newVal
 	}
 }
+
+// GetConfigForCallback 按订单号查找创建该订单时所用的支付配置（含已软删除/停用的记录）
+// 回调验签必须使用创建订单时的密钥，否则签名不匹配。
+// 若找不到 payment_config_id（旧订单或数据缺失），回退到当前激活配置。
+func (s *Service) GetConfigForCallback(ctx context.Context, orderNo string) (*model.WechatConfig, error) {
+	configID, err := s.resolvePaymentConfigID(ctx, orderNo)
+	if err != nil {
+		s.logger.Warn("回调：查询订单 payment_config_id 失败，回退激活配置",
+			zap.String("order_no", orderNo),
+			zap.Error(err),
+		)
+	}
+
+	if configID != nil {
+		cfg, err := s.store.GetByIDUnscoped(ctx, *configID)
+		if err == nil {
+			return cfg, nil
+		}
+		s.logger.Warn("回调：按 config_id 加载配置失败，回退激活配置",
+			zap.Uint("config_id", *configID),
+			zap.Error(err),
+		)
+	}
+
+	return s.GetActiveConfig(ctx)
+}
+
+// resolvePaymentConfigID 按订单号前缀从对应表中取 payment_config_id
+func (s *Service) resolvePaymentConfigID(ctx context.Context, orderNo string) (*uint, error) {
+	switch {
+	case len(orderNo) >= 3 && orderNo[:3] == "ORD":
+		order, err := s.orderStore.GetByOrderNo(ctx, orderNo)
+		if err != nil {
+			return nil, err
+		}
+		return order.PaymentConfigID, nil
+
+	case len(orderNo) >= 4 && orderNo[:4] == constants.AssetRechargeOrderPrefix:
+		record, err := s.assetRechargeStore.GetByRechargeNo(ctx, orderNo)
+		if err != nil {
+			return nil, err
+		}
+		return record.PaymentConfigID, nil
+
+	case len(orderNo) >= 4 && orderNo[:4] == constants.AgentRechargeOrderPrefix:
+		record, err := s.agentRechargeStore.GetByRechargeNo(ctx, orderNo)
+		if err != nil {
+			return nil, err
+		}
+		return record.PaymentConfigID, nil
+
+	default:
+		return nil, fmt.Errorf("未知订单号前缀: %s", orderNo)
+	}
+}