Add a systemd for linux

[vaporvee]

Idk it doesn't work for me so could you add a .service .socket systemd thing for me? Everytime i close my putty server window the Smo Server closes

[Sanae6]

There are other ways of keeping the process alive, like using tmux or screen to hold the terminal session. There is also a Docker based solution that's been created recently, though I haven't had a chance to test it myself.

I am not confident in my ability to make a good systemd file. If you want to contribute a systemd unit file, I'd be happy to look over a PR for it if someone makes one, but writing one myself is a bit much when I'm not experienced in doing so.