Cloud driver for private cloud setup

### Description

Now that the driver framework is almost finished, it would be nice with a lima driver for private cloud...

Previously we had drivers for the whole local server, but it can be handy to only allocate one VM on it?

Since we had a driver for libvirt, I _thought_ it would be handy with a driver for [oVirt](https://www.ovirt.org/) - but it was hard to do.

Better to provide a new driver for [Proxmox VE](https://www.proxmox.com/en/products/proxmox-virtual-environment/overview), which is easier to set up. It is also Open Source (AGPLv3).

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https://pve.proxmox.com/wiki/Proxmox_VE_API

* REST
* JSON

https://github.com/luthermonson/go-proxmox

Previous:

* https://github.com/lima-vm/lima/issues/2109

* https://github.com/lima-vm/lima/issues/2031

Note: the driver goes in a separate git repository

It uses the new gRPC framework, for Lima drivers.