In OpenAIRE/oai_datacite export, fix casing of creator nameIdentifier's schemeURI property and include schemeURI for all supported identifier types

Overview of the Feature Request

The OpenAIRE/oai_datacite export should use the same casing for the schemeURI property in the creator nameIdentifier property, and include schemeURI for all supported identifier types, as the DataCite/Datacite export does. Currently, when a user adds author information that includes an identifier, the OpenAIRE/oai_datacite export uses SchemeURI (capital S) instead of schemeURI, and includes it only for ORCID identifiers rather than for all supported identifier types (except DAI).

This issue is part of a larger effort to align both metadata exports, described in https://github.com/IQSS/dataverse/issues/11916 and https://github.com/IQSS/dataverse/issues/12281.

What kind of user is the feature intended for?

API User, Superuser, and Sysadmin

What inspired the request?

This is part of a larger effort to align the OpenAIRE/oai_datacite and DataCite/Datacite metadata exports. There is more context at https://github.com/IQSS/dataverse/issues/11916 and https://github.com/IQSS/dataverse/issues/12281.

What existing behavior do you want changed?

Currently, the DataCite/Datacite export uses lowercase schemeURI and includes it for all supported author identifier types (except DAI). For example:

<nameIdentifier
    nameIdentifierScheme="ORCID"
    schemeURI="https://orcid.org">https://orcid.org/0000-0001-9229-5317
</nameIdentifier>

<nameIdentifier
    nameIdentifierScheme="ISNI"
    schemeURI="http://www.isni.org">http://www.isni.org/isni/0000000121479733
</nameIdentifier>

The OpenAIRE/oai_datacite export uses SchemeURI (capital S) for ORCID identifiers only, and omits the property entirely for other identifier types. For example:

<nameIdentifier
    SchemeURI="https://orcid.org/"
    nameIdentifierScheme="ORCID">0000-0001-9229-5317
</nameIdentifier>

<nameIdentifier
    nameIdentifierScheme="ISNI">0000000121479733
</nameIdentifier>

The OpenAIRE/oai_datacite export should be changed to use lowercase schemeURI and to include it for all supported author identifier types (except DAI), matching the behavior of the DataCite/Datacite export.

Any open or closed issues related to this feature request?

• https://github.com/IQSS/dataverse/issues/11916
• https://github.com/IQSS/dataverse/issues/12281

Inspect the OpenAIRE/oai_datacite and DataCite/Datacite metadata exporters and compare their creator nameIdentifier serialization. Verify the XML output for ORCID, ISNI, and other supported identifier types, ensuring schemeURI is lowercase and present except for DAI. Confirm the result against the related alignment issues linked in the report.