add carts

app/utils/const_data/consts.go

@@ -3,3 +3,5 @@ package constdata
 // PASSWORD_VALIDATION_REGEX is used by the frontend (JavaScript supports lookaheads).
 const PASSWORD_VALIDATION_REGEX = `^(?=.*[a-z])(?=.*[A-Z])(?=.*\d).{10,}$`
 const SHOP_ID = 1
+const MAX_AMOUNT_OF_CARTS_PER_USER = 10
+const DEFAULT_NEW_CART_NAME = "new cart"