Provide open metrics for monitoring
We could provide Open Metrics (https://openmetrics.io/) to have nice graphs with grafana/prometheus for example.
Some ideas:
- nb of active SSO sessions
- nb of persistent sessions
- nb of technical sessions (CAS/SAML/OIDC/...)
- nb of registered 2FA
- nb of registered partners (SAML/CAS/OIDC)
These metrics could be hosted by portal or manager