The columns 'Created on' and 'Last activity' have been
added to the admin -> users view.

Sorting options have also been added for last activity
and the search bar has been moved to match the issues
page.

Adds gitlab.impersonation_enabled config option defaulting to true to
keep the current default behaviour.

Only the act of impersonation is modified, impersonation token
management is not affected.

Partially addresses #47424.

The status is shown for
- The author of a commit when viewing a commit
- Notes on a commit (regular/diff)
- The user that triggered a pipeline when viewing a pipeline
- The author of a merge request when viewing a merge request
- The author of notes on a merge request (regular/diff)
- The author of an issue when viewing an issue
- The author of notes on an issue
- The author of a snippet when viewing a snippet
- The author of notes on a snippet
- A user's profile page
- The list of members of a group/user

When terms are enforced, but the user has not accepted the terms
access to the API & git is rejected with a message directing the user
to the web app to accept the terms.

When a user accepts, we store this in the agreements to keep track of
which terms they accepted. We also update the flag on the user.

We will reuse the the dropdown, but exclude some menu items based on
permissions.

So moving the menu to a partial, and adding checks for each menu item here.

Make the user_link helper more generic to be used for objects other
than pipelines.