[Documentation] Please add generic (non-Docker) setup instructions

[2mac]

For those of us wishing to use other operating systems or container managers, it would be very helpful to have some generic setup instructions that don't rely on Docker.

These instructions do not need to include specific details like exact package names (which the devs cannot reasonably be expected to know for all systems); simple dependency names and preferably links to upstream software will provide enough info for experienced sysadmins to figure out what exact packages are needed.

Such instructions would be very helpful for others to create their own instructions and/or setup scripts for systems like FreeBSD or other container managers like Podman or Proxmox VE. It would even become possible to create proper packages for users to be able to install instead of having to set up Docker at all.