Allow restriction of user results from showing up in quick search and rest API searches for certain users or groups

Problem Definition

Even after restricting a user's ability to use the people directory or perform a quick search, a user can still use the REST API to locate another user's information:

rest/api/search?cql=text~"a name

Suggested Solution

We cannot restrict the API entirely as Confluence uses the same REST API for it's processes as noted in CONFSERVER-7913: Need ability to limit use of remote API to certain users, or a certain group. However, it would be useful to be able to restrict certain users or groups from receiving user results.

We have the CONFSERVER-7837: People Directory and "controlled" privacy / configure access to People Directory depending on Group membership feature request, however, this feature doesn't include results that can be pulled from the REST API.