feat(cli): add headless command-line interface

Add core.cli with argparse-based install/remove/update commands for Klipper,

Moonraker, Mainsail/Fluidd and client configs.

Wire main.py to dispatch to the CLI and fall back to the TUI when no args

are given. Pass CLI arguments through kiauh.sh and skip the update dialog

for non-interactive runs.

kiauh.sh

@@ -135,10 +135,12 @@ function main() {
    export PYTHONPATH="${entrypoint}"
 
    clear -x
-   python3 "${entrypoint}/kiauh/main.py"
+   python3 "${entrypoint}/kiauh/main.py" "$@"
 }
 
-check_if_ratos
-check_euid
-kiauh_update_dialog
-main
+# skip update prompt when arguments are passed -> dont block cli runs
+if [[ $# -eq 0 ]]; then
+  kiauh_update_dialog
+fi
+
+main "$@"