🐛 fix(subscription): avoid pre-consume lookup noise

Use a RowsAffected check for the idempotency lookup so missing records
no longer surface as "record not found" errors while preserving behavior.

model/subscription.go

@@ -838,7 +838,11 @@ func PreConsumeUserSubscription(requestId string, userId int, modelName string,
 
 	err := DB.Transaction(func(tx *gorm.DB) error {
 		var existing SubscriptionPreConsumeRecord
-		if err := tx.Where("request_id = ?", requestId).First(&existing).Error; err == nil {
+		query := tx.Where("request_id = ?", requestId).Limit(1).Find(&existing)
+		if query.Error != nil {
+			return query.Error
+		}
+		if query.RowsAffected > 0 {
 			if existing.Status == "refunded" {
 				return errors.New("subscription pre-consume already refunded")
 			}