Fix transliteration for metadata + transliterate select options (#5430)

## Context 
Fixes #5403

Transliteration is now integrated to form validation through the schema.
While it does not impede inputting an invalid value, it impedes
submitting a form that will fail as the transliteration is not possible.
Until then we were only performing the transliteration at save time in
the front-end, but it's best to provide the information as soon as
possible. Later we will add helpers to guide the user (eg "This name is
not valid": https://github.com/twentyhq/twenty/issues/5428).

---------

Co-authored-by: Charles Bochet <charles@twenty.com>

packages/twenty-server/src/engine/metadata-modules/field-metadata/validators/is-valid-graphql-enum-name.validator.ts

@@ -4,7 +4,7 @@ import {
   ValidationArguments,
 } from 'class-validator';
 
-const graphQLEnumNameRegex = /^[_A-Za-z][_0-9A-Za-z]+$/;
+const graphQLEnumNameRegex = /^[_A-Za-z][_0-9A-Za-z]*$/;
 
 export function IsValidGraphQLEnumName(validationOptions?: ValidationOptions) {
   return function (object: object, propertyName: string) {