Improve informativeness of the @ mention of a group

Release notes

Problem to solve

When in a comment, a @groupname is mentioned, it gets hyperlinked to the /groupname overview page which shows its subgroups and projects. However, might it be more likely that one would want to check who the direct members are, i.e. who exactly got mentioned?

IMHO, that would esp. be true when the group does not actually content, but is mostly an alias to be @-mentioned.

Proposal

1. (MVC) Route/link to /-/group_members?with_inherited_permissions=exclude instead.
2. (iteration idea) Add logic to check for subgroups & projects, and then route to either the overview page, or the members page by some to-be-determined criteria.
3. (iteration idea) Add front-end popup to list the direct group members on hover, while leaving the hyperlink to the group overview page for clicking.

Intended users

Feature Usage Metrics

Fewer click tracks from /groupname overview page to Manage > Members > /groups/…/-/group_members > Membership filter

Does this feature require an audit event?

No.

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