Create a standalone User Roles reference covering all six roles (Owner,
Admin, Network Admin, Billing Admin, Auditor, User) with a permission
matrix aligned to the current dashboard, per-role sections, API/token
notes, and role-assignment steps.
Reduce the role section on the Add Users page to a pointer (keeping the
existing anchor), repoint inbound links from delete-account,
control-center, and msp-portal, add the page to the Team sidebar, and
refresh the role screenshots.