feat(grub): rebuild on every wallpaper change via udt-grub

GRUB's background is a wallpaper snapshot, but only install.sh rebuilt it,
so a wallpaper change left the /boot copy stale with no hint. udt-grub now
holds the build-and-print logic; install.sh runs it in the foreground and
udt-accent starts it detached next to udt-homepage. A stale installed theme
gets a notification carrying the root copy command. A flock serialises the
two runs install.sh triggers, since build swaps dist/udt in by rename.

AGENTS.md: udt-accent writes seven outputs (SDDM was missing), and names
the two detached helpers.

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

1 files changed, 6 insertions, 29 deletions

diff --git a/install.sh b/install.sh
index b63f8c4..33e6f0c 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-machine-name udt-powermenu.sh udt-launcher.sh qar-scrotmenu.sh; do
+for f in udt-accent udt-grub udt-palette udt-machine-name udt-powermenu.sh udt-launcher.sh qar-scrotmenu.sh; do
     ln -sfn "$repo/bin/$f" "$HOME/bin/$f"
 done
 
@@ -339,34 +339,11 @@ if [ -d "$sddm_repo/theme" ]; then
     echo "  printf '[Theme]\\nCurrent=udt\\n' > /etc/sddm.conf.d/udt.conf"
 fi
 
-# GRUB. Same shape as SDDM: udt-palette has rendered theme.txt, the sibling
-# repo's build assembles the theme as the user, and the root half is printed.
-# A copy, not a link: GRUB reads /boot before /home is mounted. The background
-# is a snapshot of the wallpaper, so the copy needs rerunning after a scheme
-# or wallpaper change; grub-mkconfig only when GRUB_THEME changes.
-grub_repo="$(realpath -m "$repo/../grub-theme-udt")"
-if [ -x "$grub_repo/build" ]; then
-    if "$grub_repo/build"; then
-        grub_theme='/boot/grub/themes/udt/theme.txt'
-        echo
-        if diff -rq "$grub_repo/dist/udt" /boot/grub/themes/udt >/dev/null 2>&1; then
-            echo "grub theme: up to date"
-        elif grep -q "^GRUB_THEME=\"$grub_theme\"" /etc/default/grub 2>/dev/null; then
-            echo "grub theme: refresh as root"
-            echo "  rm -rf /boot/grub/themes/udt && cp -r \"$grub_repo/dist/udt\" /boot/grub/themes/"
-        else
-            echo "grub theme: run these as root to install or refresh it"
-            echo "  rm -rf /boot/grub/themes/udt && cp -r \"$grub_repo/dist/udt\" /boot/grub/themes/"
-            echo "  # once: GRUB_THEME=\"$grub_theme\" in /etc/default/grub, then"
-            echo "  grub-mkconfig -o /boot/grub/grub.cfg"
-        fi
-        # The panel title falls back to the OS name until one is set.
-        [ -n "$("$repo/bin/udt-machine-name")" ] || \
-            echo "  # optional, the panel title: sudo \"$repo/bin/udt-machine-name\" \"My Machine\""
-    else
-        echo "grub: its build failed, theme not refreshed" >&2
-    fi
-fi
+# GRUB. Same shape as SDDM: udt-palette has rendered theme.txt, and udt-grub
+# builds the theme as the user and prints the root half. udt-accent also runs
+# it, detached, so a wallpaper change alone rebuilds it too.
+echo
+"$repo/bin/udt-grub"
 
 [ -n "$reloaded" ] && echo "reloaded:$reloaded"