Goodbye Flatpak Sunshine. Hello AppImage.
Until a deb package is available for Debian Bookworm, we can just run sunshine as an AppImage.
It is faster to startup and is a little less bloated.
The goal here is to run Sunshine as a service managed by supervisord so that it is kept running and is restarted automatically if stopped.
Xorg was starting before udev could finish the monitor command. This prevented the X server from having access to the input devices. For some reason, any subsequent starts would be fine.
Adding a small delay to the X server start and triggering a request for device events from the kernel after a delay seems to fix this issue.