[ENH] - Expose Backup and Restore for Conda-Store API

[pt247]

Feature description

Backup and Restore RFD

Expose conda-store REST API to authenticated nebari Admin. There are a few endpoints in conda-store API that point towards artifacts. We need to make sure that we provide links for users to download these instead of the default path that the conda-store API provides.

Value and/or benefit

This will allow admins to query/backup/restore conda-store.

Anything else?

META issue: #2518

[kcpevey]

Related backup and restore conda-store issue: https://github.com/conda-incubator/conda-store/issues/854