[Request] Please add a simple kiosk/fullscreen mode for v1

[Conan-Kudo]

Magpie version

1.0~git20231126.e106dfe

Use-cases

For the Fedora Budgie spin, we need a way for the Budgie Wayland compositor to be able to run an application full screen for two particular reasons:

1. To function as the compositor for a login manager greeter (e.g. SDDM, greetd, etc.)
2. To be able to run Anaconda Initial Setup

Without this ability, we would be forced to ship two compositors on the spin, which is certainly not great.

Proposal

I would suggest somewhat mimicking KWin's mechanism for this by providing a flag for launching Magpie with a single application and to automatically shut down when that application quits and forward that application's exit code. This makes it very easy to support single-application use-cases. Failing that, some kind of way to have an alternate configuration file that lets you tell the compositor you are launching a single application and then quitting after it exits would work too.

References

• KDE Plasma's SDDM configuration to use KWin
• Fedora KDE's stub to use KWin for initial-setup-gui
• Fedora Sway's SDDM configuration to use Sway
• Fedora Sway's stub to use Sway for initial-setup-gui
• Anaconda Initial Setup's stub to use Weston for initial-setup-gui

[serebit]

As far as I'm concerned, it's up to the application to size its surfaces properly and avoid decorations. I can easily add an option to attach to the lifecycle of a subprocess, though.

[serebit]

Fixed with #18. I don't know why Fedora CI is exploding, Alpine is fine and it works on my Arch machine.