优化号主交接超时卡死问题

- 号主交接超时(owner_timeout)后允许补提交交接说明，避免临时延误导致订单卡死
- 后台新增"重置交接"动作，可将超时订单恢复为待号主交接并刷新计时
- 交接超时改以进入待交接时刻为基准计算，新增 handoff_started_at 字段

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

backend/internal/modules/order/admin_actions.go

@@ -8,6 +8,7 @@ import (
 	"hfb_sys/backend/internal/modules/notification"
 
 	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
 )
 
 func (r *Repository) AdminClose(ctx context.Context, adminID uint64, orderID uint64, req AdminActionRequest, meta AuditMeta) error {
@@ -162,6 +163,54 @@ func (r *Repository) AdminMarkAbnormal(ctx context.Context, adminID uint64, orde
 	})
 }
 
+// AdminResetHandoff 将号主交接超时（owner_timeout）的订单重置回待号主交接，并刷新交接计时，
+// 让客服可以给号主再次提交交接说明的机会，避免订单卡死在超时状态。
+func (r *Repository) AdminResetHandoff(ctx context.Context, adminID uint64, orderID uint64, req AdminActionRequest, meta AuditMeta) error {
+	return r.db.WithContext(ctx).Transaction(func(tx *gorm.DB) error {
+		var order model.RentalOrder
+		if err := tx.Clauses(clause.Locking{Strength: "UPDATE"}).First(&order, orderID).Error; err != nil {
+			return err
+		}
+		if order.Status != orderStatusPendingHandoff || order.HandoffStatus != handoffStatusOwnerTimeout {
+			return ErrOrderCannotResetHandoff
+		}
+		beforeHandoffStatus := order.HandoffStatus
+		now := time.Now()
+		order.HandoffStatus = handoffStatusPendingOwner
+		order.HandoffStartedAt = &now
+		if err := notification.Append(tx,
+			notification.Entry{
+				UserID:  order.OwnerID,
+				Type:    "order_admin",
+				Title:   "请重新提交交接说明",
+				Content: "客服已重置交接状态，请尽快提交交接说明，避免再次超时。原因：" + req.Reason,
+				BizType: "order",
+				BizID:   &order.ID,
+			},
+			notification.Entry{
+				UserID:  order.RenterID,
+				Type:    "order_admin",
+				Title:   "订单交接已重置",
+				Content: "客服已重置交接状态，正在等待号主重新提交交接说明。原因：" + req.Reason,
+				BizType: "order",
+				BizID:   &order.ID,
+			},
+		); err != nil {
+			return err
+		}
+		if err := appendAuditLog(tx, adminID, "order.reset_handoff", "order", order.ID, meta, map[string]any{
+			"order_id":              order.ID,
+			"order_no":              order.OrderNo,
+			"reason":                req.Reason,
+			"before_handoff_status": beforeHandoffStatus,
+			"after_handoff_status":  order.HandoffStatus,
+		}); err != nil {
+			return err
+		}
+		return tx.Save(&order).Error
+	})
+}
+
 // AdminRefund 触发后台人工退款，退款由 payment 模块走渠道原路退回。
 func (r *Repository) AdminRefund(ctx context.Context, orderID uint64) (*RefundStatusDTO, error) {
 	var order model.RentalOrder