feat(bin): udt-machine-name writes PRETTY_HOSTNAME to /etc/machine-info

The GRUB theme titles its panel with the machine's pretty name, and on
Slackware nothing writes /etc/machine-info: hostnamectl is systemd's. This
sets the one key, keeping any others, and with no argument prints it.

The value is double-quoted with only \ and " escaped, the escapes systemd's
reader and the GRUB build's shlex agree on; control characters are refused.
It needs root and is never run by install.sh, which only suggests it in the
GRUB output while no name is set. tests/machine-name.sh checks the quoting
round-trip against shlex.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/install.sh b/install.sh
index 8052f71..f8ae97b 100755
--- a/install.sh
+++ b/install.sh
@@ -104,7 +104,7 @@ ln -sfn "$HOME/.cache/udt/colors.json" "$HOME/.cache/wal/colors.json"
 
 # The rofi menus are bound by name in hypr-theme's keybindings, so they keep
 # the names they had when they lived loose in ~/bin.
-for f in udt-accent udt-palette udt-powermenu.sh udt-launcher.sh qar-scrotmenu.sh; do
+for f in udt-accent udt-palette udt-machine-name udt-powermenu.sh udt-launcher.sh qar-scrotmenu.sh; do
     ln -sfn "$repo/bin/$f" "$HOME/bin/$f"
 done
 
@@ -352,6 +352,9 @@ if [ -x "$grub_repo/build" ]; then
         echo "  rm -rf /boot/grub/themes/udt && cp -r \"$grub_repo/dist/udt\" /boot/grub/themes/"
         echo "  # once: GRUB_THEME=\"/boot/grub/themes/udt/theme.txt\" in /etc/default/grub, then"
         echo "  grub-mkconfig -o /boot/grub/grub.cfg"
+        # The panel title falls back to the OS name until one is set.
+        [ -n "$("$repo/bin/udt-machine-name")" ] || \
+            echo "  # optional, the panel title: sudo \"$repo/bin/udt-machine-name\" \"My Machine\""
     else
         echo "grub: its build failed, theme not refreshed" >&2
     fi