[ENH] Enable auth passthrough between all integrated apps

[iameskild]

Feature description

For many of Nebari's core features, even if you've authenticated with JupyterHub, you will be prompted to login back again if you navigate to another app, which is not a great user experience.

At minimum this affects:

• conda-store
• argo-workflows
• dask dashboard (+ lab extension)
• keycloak (as an admin)
• ...

This auth passthrough should handle both the login and logout.

Value and/or benefit

Improve user experience.

Anything else?

No response