So the following failed to fix:
# rm -rf /etc/pacman.d/gnupg or mv /etc/pacman.d/gnupg /etc/pacman.d/gnupg-broken
# pacman-key --init
# pacman-key --populate artix
# pacman-key --refresh-keys
So pacman -Syu works but only kparts package from the build-bot appears to be having issues.
I just tried to install kparts without any issue at all from the "https://mirror.clarkson.edu/artix-linux/repos/$repo/os/$arch " mirror in the /etc/pacman.d/mirrorlist. Maybe delete the downloaded version and edit the /etc/pacman.d/mirrorlist use the same mirror as above and try again. Just encase the download from the mirror being used failed somehow before.
# rm -rf /var/cache/pacman/pkg/kparts-5.101.0-1-x86_64.pkg.tar.zst{,.sig}
# pacman -Syyu kparts
"The extra "y" will cause the rebuild of the repositories database cache in /var/lib/pacman/sync."
Hopefully this will address the issue.
In the worse case one could obtain the PKGBUILD for kparts from Artix's package website and create the package yourself then install it manually. I would recommend creating a folder for your collection of PKGBUILD files and folders for example "/home/<user home folder>/factory".
$ git clone https://gitea.artixlinux.org/packagesK/kparts.git
$ cd kparts/x86_64/extra/
$ makepkg -i