Add a group admin UI to add/remove members

(Moved out of #542 (closed))

Group list view in user menu (!1688 (merged))
Group display view (!1688 (merged))
Group edit view that can only add/remove users (including self) and assign them roles (!1688 (merged))
Pagination on group members list (!1693 (merged))
Audit log on group membership changes (!1701 (merged))
Show audit log in UI (!1703 (merged))

Edited Mar 24, 2025 by Enrico Zini

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