Difficult to find users to delete from group in large groups

[MarieVerdonck]

Is your feature request related to a problem? Please describe. Difficult to find users to delete from a group when large number of members

Describe the solution you'd like The fixes for

• https://github.com/DSpace/DSpace/issues/9052
• https://github.com/DSpace/dspace-angular/issues/2512

split the members list of a group into current members and not-yet-in-group list of searchable members to solve issues loading members of large groups.

But this currently makes it very hard to remove a specific member from a group with a large number of members:

• The list of current members is not searchable or logically (eg alphabetically on name or email) sorted, so to find a member to delete you have to page through pages & find them
• On the EPerson page itself you can not remove the user either, it just lists the groups (as links to the group page) the user is a member of

Ideally the list of current members on the edit group page is searchable; and the Edit EPerson page allows (admins) to delete person from groups it is a member of without having to go to that group page.