look at the last 2 commits for a real changelog

i accidentally changed checkout to v4 (i'll keep it that way), but forgot to change upload-artifact to v4 which was the issue of the failing workflows

add support for more firmwares

fix typo in code

Merge remote-tracking branch 'upstream/master'

fix the update checker

fix offests.h for stage2

adjust makefile again, should work now

overhauled the GUI

adjust makefile again, should work now

Improve workflow