Provide checksum check on uncommited upload that is transformed into a content unit

Is your feature request related to a problem? Please describe.
In https://github.com/pulp/pulpcore/issues/5875 we had a discussion about that it is no longer allowed to list artifacts.

That lead to the point that if you want a chunked upload transform in a content unit you should call one of the following on an uncommitted upload
https://pulpproject.org/pulp_file/restapi/#tag/Content:-Files/operation/content_file_files_create
https://pulpproject.org/pulp_rpm/restapi/#tag/Content:-Packages/operation/content_rpm_packages_create

One of the benefits of the /commit step of the chunked upload was that you could verify the end result with a checksum. This is no longer possible in the new scenario

Describe the solution you'd like
Option to pass a checksum when an uncommitted upload is transformed in a content unit. I guess it could also benefit regular uploads and file_url's to have a checksum verification

Describe alternatives you've considered
None

Additional context
This is a consequence of not allowing non admins to list artifacts and allow artifacts to change in content units

Start with the linked content_file_files_create and content_rpm_packages_create REST operations and the discussion in issue 5875. Define how a checksum is supplied and verified when an uncommitted upload becomes a content unit, including whether regular uploads and file URLs are covered; done means the requested checksum validation is supported and tested.