How to set up OIDC Session Management in PAS 4.7 (as the OpenID Provider)
To set up OIDC Session Management in PAS 4.7, just configure your OIDC OP with the property "check_session_iframe" and make it have the value "https://<your-domain-here>/oidc/authenticate/check_session/". This allows Relying Parties to fetch the OP iframe from PAS, which will handle the session management on the OP side.
Additionally, your OIDC authenticator (OIDCToSAMLBroker, or other OIDC authenticators) will need to have the config property "useSessionManagement" : "true". Otherwise it will not return session_state which the RP will need to send to the OP iframe.
After that, you are all set, provided that your RP is correctly set up for OIDC session management.