Check OIDC user session state in frontend

Once a web application user is logged in using OpenID Connect, the state of his session must be regularly checked (see OpenID Connect Session Management).

When a session has expired, a silent renewal can be performed or a simple redirect to the logout page instead.

We could use the oicd-client.js library to ease the implementation.

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Migrated from T2248 (view on Phabricator)