feat: 技术债务清理（支付配置动态化、API文档补全、轮询常量提取、废弃代码清理）

internal/model/dto/refund_dto.go

@@ -63,6 +63,7 @@ type RefundResponse struct {
 	ApprovedRefundAmount  *int64 `json:"approved_refund_amount,omitempty" description:"审批实际退款金额（分）"`
 	RefundReason          string `json:"refund_reason" description:"退款原因"`
 	Status                int    `json:"status" description:"状态 (1:待审批, 2:已通过, 3:已拒绝, 4:已退回)"`
+	StatusName            string `json:"status_name" description:"状态名称（中文）"`
 	ProcessorID           *uint  `json:"processor_id,omitempty" description:"审批人ID"`
 	ProcessedAt           string `json:"processed_at,omitempty" description:"审批时间"`
 	RejectReason          string `json:"reject_reason,omitempty" description:"拒绝原因"`