Since the static binaries provided upstream are no longer working on newer RaspiOS or on 32bit ARM, create a standard scriptmodule to build Pegasus with `pegasus-fe-dev`. The new scriptmodule is meant to work similarly to the `es`/`es-dev` pair, only one can work at a time and they share a set of common functions.
Modified the original scriptmodule and added a theme download function, using @mmatyas's themes. More can be found at [2].
Notes:
* the `pegasus-fe` launcher doesn't need the previous TTY set-up, it's now handled by `runcommand`.
* sometimes the `/dev/dri/card0` is not the right card node since the order of the `cardX` inodes is not guaranteed.
Find the right card node dynamically (see [1]) and tell Qt about it with a minimal config file used in the launcher
[1] https://forums.raspberrypi.com/viewtopic.php?t=351263
[2] https://github.com/mmatyas/pegasus-theme-gallery-db/blob/master/repos.txt
