limit maximum count of tags in a transaction

pkg/api/transactions.go

@@ -646,6 +646,10 @@ func (a *TransactionsApi) TransactionCreateHandler(c *core.WebContext) (any, *er
 		return nil, errs.ErrTransactionTagIdInvalid
 	}
 
+	if len(tagIds) > 10 {
+		return nil, errs.ErrTransactionTagTooMuch
+	}
+
 	pictureIds, err := utils.StringArrayToInt64Array(transactionCreateReq.PictureIds)
 
 	if err != nil {
@@ -772,6 +776,10 @@ func (a *TransactionsApi) TransactionModifyHandler(c *core.WebContext) (any, *er
 		return nil, errs.ErrTransactionTagIdInvalid
 	}
 
+	if len(tagIds) > 10 {
+		return nil, errs.ErrTransactionTagTooMuch
+	}
+
 	pictureIds, err := utils.StringArrayToInt64Array(transactionModifyReq.PictureIds)
 
 	if err != nil {

pkg/errs/transaction_tag.go

@@ -10,4 +10,5 @@ var (
 	ErrTransactionTagNameAlreadyExists    = NewNormalError(NormalSubcategoryTag, 3, http.StatusBadRequest, "transaction tag name already exists")
 	ErrTransactionTagInUseCannotBeDeleted = NewNormalError(NormalSubcategoryTag, 4, http.StatusBadRequest, "transaction tag is in use and cannot be deleted")
 	ErrTransactionTagIndexNotFound        = NewNormalError(NormalSubcategoryTag, 5, http.StatusBadRequest, "transaction tag index not found")
+	ErrTransactionTagTooMuch              = NewNormalError(NormalSubcategoryTag, 6, http.StatusBadRequest, "transaction tags too much")
 )