Keep window open after launching app

[ghost]

Pretty much the title. I'd like to keep a single instance of sirula open, as a non layer-shell window.
that way I can keep it open and use it somewhat like a dock to launch multiple apps without closing.

An option for using layer-shell or not isn't necessarily what I'm asking for, as my compositor doesn't support it so it already fallbacks to a normal window, however if you think it's fitting then that could be a cool option too.

[DorianRudolph]

I'm happy to accept a pull request, but this is not a feature I'm interested in working on right now.