Choose who can check in late arrivals

The Role & access tab for a professional now has a separate **Check in after
the late-arrival cutoff** option. Their ordinary roster permission still
controls which classes they can open; this option only extends the check-in
window for classes they already have permission to manage.

The venue-wide cutoff remains the default for everyone without this grant.
Removing the grant takes the professional back to that normal cutoff without
changing their role or access to their assigned class rosters.