21:03:58 [1]: [PYTHON JOB]: "Mode: 0o755"
error: target not found: lxqt-common
warning: skipping target: compton
warning: skipping target: network-manager-applet
warning: skipping target: powertop
warning: skipping target: xdg-user-dirs
warning: skipping target: xdg-utils
warning: skipping target: terminus-font
21:04:06 [0]: Running "chroot" ("/tmp/calamares-root-xvn4bnzk", "pacman-key", "--init")
21:04:06 [0]: Finished. Exit code: 127
21:04:06 [0]: Target cmd ("pacman-key", "--init")
21:04:06 [0]: Target out "chroot: failed to run command ‘pacman-key’: No such file or directory"
21:04:06 [0]: Running "chroot" ("/tmp/calamares-root-xvn4bnzk", "pacman-key", "--populate", "archlinux", "artix")
21:04:06 [0]: Finished. Exit code: 127
21:04:06 [0]: Target cmd ("pacman-key", "--populate", "archlinux", "artix")
21:04:06 [0]: Target out "chroot: failed to run command ‘pacman-key’: No such file or directory"
From the looks of the log, it seems the pacman failed to find lxqt-common. Can you try check the contents of /etc/pacman.d/mirrorlist and /etc/pacman.d/mirrorlist-arch
Also, while you're at live session, run the command sudo pacman -Syyu in there and paste the output of it. I have feeeling the installation fails because of pacman errors itself...