> Is it open source though?
The important bits already are and you can easily do this yourself, as long as you are not interesting in spawning new instances.
Setup tirgervnc on a system and then just point noVNC at it.
The only thing really lacking is a means to route a users VNC session to the proper backend. But that could easily be accomplished via something that dynamically sets up noVNC.
Personally I use tigerVNC over SSH via port forwarding.
Well you could run Scribus under VNC (like you could any software, e.g. Inkscape, Libre Office) and then people could go into the VNC session and run it, they would sharing the single instance and would have to be mindful not to step on each other's activity. Or, if you have a limited number of people, say 20, each could have a VNC session (:1 - :20) where they'd run their own Scribus session. But I'm probably going beyond what you originally wanted with this suggestion.
You don't know how vncserver works. It's not a service that spawns processes. You start vncserver with a display parameter and then you are able to connect to that display. When you want that display gone you call vncserver -kill. I assure you, you have vncserver. Xvnc is just a wrapper for being both an X server and a VNC server.
http://tigervnc.org/doc/Xvnc.html
I can see you aren't particularly interested in learning how to use the tools you have, so we'll leave it at this.
http://tigervnc.org/ TigerVNC , é um aplicação cliente e servidor VNC.Começou como um fork do TightVNC e atualmente é a implementação VNC padrão do Fedora.
Instalação: -Manjaro/Arch: pacman -S tigervnc ; -Ubuntu/Debian: apt-get install tigervnc ;
Iniciando: Basta usar seguinte comando no terminal: vncserver ;