Enable data validation extension to a field

[johardi]

This feature enables template designers to bind a field with an extension (i.e., external service) for custom data validation. We will outline the extension's specifications to ensure security and prevent misuse.

[johardi]

The extension could function as an authoritative verification service that authenticates IDs that are associated to the metadata. For instance, when users input an ORCID number, the service verifies its validity and, upon confirmation, issues a badge as a symbol of certification.