Additional metadata fields for Client Identifier Documents

I've been reading through some issues and other specifications, and I'm wondering if it would make sense or be possible for us to define some additional fields for the Client Identifier documents. In the SAI working group, they have the concept of an application description and application author. I think the latter is covered by the contacts field in the Client Identifier documents, but the former, a description of the client is currently only kind of covered by the client_uri value (the homepage).

I think it'd make sense to add a string value of client_description to the client identifier documents, I'm not sure if this is something this spec can do, as from what I understand it, the fields need to be registered in the IANA Registry, however, I think from a user perspective, being able to see a short textual description of the application may be helpful when displaying the consent screen.

This would, I think, reduce the gap between solid-oidc and SAI's need for an application profile document, as noted in https://github.com/solid/data-interoperability-panel/issues/210#issuecomment-953736998

(addendum: I did try to find an existing issue prior to opening this one, but didn't find anything that concretely was this specifically).

Start by reviewing the Client Identifier document metadata and the linked IANA OAuth client metadata registry entry. Then compare the proposed client_description with the SAI application profile discussion linked in the issue; done would require an agreed specification change and confirmation of the registration path.