Doorman Improper Access Control Allows Privilege Escalation

Improper access control in Doorman v0.1.0 and v1.0.2 allows any authenticated user to update their own account role to a non-admin privileged role via /platform/user/{username}. The `role` field is accepted by the update model without a manage_users permission check for self-updates, enabling privilege escalation to high-privileged roles.