Note Editor: make sure we show only the assigned reviewers as selectable readers

[melisabok]

Currently the comment invitation has this configuration for the selectable readers:

    "readers": {
      "param": {
        "enum": [
          "colmweb.org/COLM/2024/Conference/Program_Chairs",
          "colmweb.org/COLM/2024/Conference/Submission220/Reviewer_.*",
          "colmweb.org/COLM/2024/Conference/Submission220/Area_Chairs",
          "colmweb.org/COLM/2024/Conference/Submission220/Reviewers",
          "colmweb.org/COLM/2024/Conference/Submission220/Reviewers/Submitted"
        ]
      }
    }

If a reviewer is unassigned then the reviewer id will show up in the option to select the readers. This is confusing because an AC doesn't know if that reviewer is assigned or not.

I suggest to the filter out the anon ids that are not members of the reviewer group. How?

Option 1: the UI should get the groups by prefix and make sure they are all members of the /Reviewers group. This should assume the /Reviewers group will be able in the enum.

Option 2: Change the enum definition for anon ids and use the following syntax:

colmweb.org/COLM/2024/Conference/Submission220/Reviewers:members

The UI will query the group by id parsing the name until the : and show all the members of the group.

Other suggestions? @xkopenreview @carlosmondra