Summary:
This gives more guidance to users when editing document shares in the UserManager dialog.
* For a document on a team site, any shares with team members are marked `Team member`.
* Shares that count as external collaborators are marked for documents on a team or personal site as `collaborator` (personal site) or `outside collaborator` (team site).
* Collaborators are marked `1 of 2`, `2 of 2`, and then `limit exceeded`.
* On a team site, links are offered for each collaborator to add them to the team. The links lead to a prefilled dialog for managing team membership which can be confirmed immediately, allowing the user to continue without interruption.
* On a personal site, for the last collaborator and beyond, a link is added for creating a team. This isn't seamless since creating a team involves billing etc.
There's a small unrelated tweak in tests to remove a confusing import from `test/browser` in `test/server`.
One thing I didn't get to is checking if owner of doc is owner of site. If they aren't, they may try to add a member and be denied at that point - it would be more polite to change messaging earlier for them.
Test Plan: added and updated tests
Reviewers: georgegevoian
Reviewed By: georgegevoian
Differential Revision: https://phab.getgrist.com/D3083
