DISCORD_ALLOWED_ROLES was checked by the Discord adapter (_is_allowed_user)
but gateway._is_user_authorized only read DISCORD_ALLOWED_USERS, so
role-authorized users were rejected with "Unauthorized user" at the
gateway layer despite passing the adapter gate.
- Add role_authorized: bool = False to SessionSource
- Add role_authorized param to build_source (base.py)
- Compute _role_authorized in on_message when user passes via role not user ID
- Thread _role_authorized through _handle_message -> build_source
- Check source.role_authorized early in _is_user_authorized (run.py)
Fixes#33952
e5580f43c2