for a user not in SRO (current default case for live users)
- Application redirects to CoSign for Authentication
- CoSign authenticates user
- Cosign redirects user to application
for a user in SRO (interim state after user migration, but before application migration)
- Application redirects to CoSign for Authentication
- CoSign forwards user to Entra for authentication
- Entra authenticates user (quirk: Entra registration requires member user)
- Entra redirects user to CoSign
- Cosign redirects user to application
Right now, we don't direct friend users via the staged rollout path, but we could.
TODO: Allow friend users to be directed to Entra, as if they were in staged rollout