fix(scripts): report the grub.cfg default entry, and stop claiming what was checked

The pending-entry grep anchored on "menuentry 'Ubuntu'" with -A4 and matched no
linux line, so the script printed nothing where it should have shown the next
boot's command line; the PENDING line then said "is in grub.cfg" when the loop
only ever compared the tracked file against /proc/cmdline. Now the default
entry's linux line is parsed with awk (first linux line of the first Ubuntu
menuentry, which is what GRUB_DEFAULT=0 selects), its iommu token is printed,
and a mismatch against the tracked file warns by name.

scripts/set-dankclaw-bootline.sh

@@ -46,8 +46,14 @@ else
   sudo update-grub
 fi
 
-echo "== pending entry"
+# The DEFAULT entry is the first 'Ubuntu' menuentry's linux line: that is the
-sudo grep -m1 "menuentry 'Ubuntu'" -A4 /boot/grub/grub.cfg | grep -m1 linux | tr ' ' '\n' | grep -E '^(iommu|amd_iommu)' || true
+# command line the next boot actually gets. (GRUB_DEFAULT=0 here, so first it is.)
+echo "== grub.cfg default entry"
+CFG="$(sudo awk '/menuentry .Ubuntu/ && !seen {seen=1}
+                 seen && /^[[:space:]]*linux/ {print; exit}' /boot/grub/grub.cfg)"
+[ -n "$CFG" ] || { echo "could not read the default linux line from grub.cfg" >&2; exit 1; }
+printf '%s\n' "$CFG" | tr ' \t' '\n' | grep -E '^(iommu|amd_iommu)=' || echo "(no iommu token in the default entry)"
+
 echo "== running kernel"
 tr '\0' ' ' < /proc/cmdline; echo
 
@@ -56,9 +62,14 @@ NOW="$(cat /proc/cmdline)"
 for tok in $WANT; do
   case " $NOW " in
     *" $tok "*) ;;
-    *) echo "PENDING: '$tok' is in grub.cfg but not in the running kernel — needs a reboot" ;;
+    *) echo "PENDING: '$tok' is not in the running kernel" ;;
   esac
 done
+WANT_IOMMU="$(printf '%s\n' $WANT | grep -E '^(iommu|amd_iommu)=' | head -1)"
+CFG_IOMMU="$(printf '%s\n' "$CFG" | tr ' \t' '\n' | grep -E '^(iommu|amd_iommu)=' | head -1)"
+if [ "$WANT_IOMMU" != "$CFG_IOMMU" ]; then
+  echo "WARN: grub.cfg default entry says '${CFG_IOMMU:-none}', tracked file says '${WANT_IOMMU:-none}'" >&2
+fi
 
 if [ "$REBOOT" = 1 ]; then
   echo "== rebooting now"