juliaup in a multi-user environment

We would like to install Juliaup as root on a departmental Linux cluster and have it available to users. I haven't found any documentation specific to this use. I presume we should use a custom installation but I am not entirely clear what directories would go where. For a personal installation the are both ~/.juliaup and ~/.julia/juliaup directories created. What would be system-wide equivalents?

Start by reviewing juliaup's existing personal-installation behavior and the requested custom installation on a multi-user Linux cluster. Document the system-wide directory equivalents and root/user setup, with the work complete when administrators can install juliaup for shared user access without relying on personal-directory assumptions.

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