I’ve never seen a significant benefit to such a feature. TrueNAS has it, and I never use it. Proxmox has it, and I never use it there either (for the host itself; I use the virtual console for the VMs all the time). What’s the benefit compared to just ssh user@host? Every halfway modern operating system (yes, including Windows since Windows 10) has an ssh client–opening a terminal window and running it has to be faster than opening a browser, browsing to the NS8/Cockpit/whatever web UI, logging in there, and then browsing to the web shell.
Heavens no; it would be silly to do either of these. I would give you a SSH public key, keeping the private key, well, private. You’d either temporarily add that to the root user (echo $key >> /root/.ssh/authorized_keys), or (better, but a little more work) to a different user with sudo access. It’s a different process than doing it through the GUI to be sure, but I don’t see that it’s any more cumbersone.
But that seems kind of a convoluted way to copy over a public key. If your client is anything but Windows, the simplest way to do it is with ssh-copy-id user@host. If your client machine is running Windows, it doesn’t look like that command is available for some reason, but in that case, ssh to the host, nano .ssh/authorized_keys, and then paste in the public key. The scp seems like an unnecessary step in any case.
Since NS8 doesn’t deal with system-level users at all, I’d say probably not. But it looks like this can be done through Cockpit as well.
As has been discussed several times, NS8 doesn’t include any tools to manage the server itself. Installing updates? Not there. Configuring the network? Not there. System-level user management? Not there either. Heck, even shutting down the system isn’t there. And while I don’t love that fact, and I’m not sure (easy for me to say) it would be a huge amount of development work to figure out which of the two supported distros (because there really only are two: Debian and EL) is being used, and adapt accordingly, that’s the way it’s designed.
So, come up with other ways of managing the system. Use the CLI–it isn’t too hard for the basic tasks that are likely to be necessary. Or install some other tool, like Cockpit or Webmin.
…but Stephane has suggested–in this very thread, no less–installing Cockpit with NS8. That’s additional software that isn’t part of the base distro, nor is it part of NS8. And it’s never been the case with NS7 that you can’t install any software other than NS modules–though in both cases, you’re on your own to ensure they don’t interfere with the rest of what the system’s doing.
But with respect to SSH specifically, this whole thread strikes me as odd. SSH is fundamentally a command-line tool. There are mature tools for configuring and managing it at the command line. I don’t understand the desire for a GUI way to configure/use a command-line tool. Not that it’s bad as such, but I just don’t see why it’s particularly desirable.