Fail closed when passwordless sudo expiry cannot arm

Remove stale passwordless sudo grants during boot and revoke a live grant immediately if its transient expiry timer cannot be created. Exercise both failure paths and the shipped tmpfiles rule against a disposable root.

Co-authored-by: Adolanium <94890352+Adolanium@users.noreply.github.com>

bin/omarchy-sudo-passwordless

@@ -13,6 +13,19 @@ if [[ $1 && ! $1 =~ ^[0-9]+$ ]]; then
   exit 1
 fi
 
+arm_expiry() {
+  if sudo systemd-run --on-active=${MINUTES}m --timer-property=AccuracySec=1s --unit="$TIMER_NAME" \
+    rm -f -- "$NOPASSWD_FILE"; then
+    return 0
+  fi
+
+  echo "Failed to schedule passwordless sudo expiry. Revoking access now." >&2
+  if ! sudo rm -f -- "$NOPASSWD_FILE"; then
+    echo "CRITICAL: Could not remove $NOPASSWD_FILE. Remove it as root immediately." >&2
+  fi
+  return 1
+}
+
 echo "Toggle passwordless sudo..."
 
 # Safety: if the file exists but the timer doesn't (e.g. after reboot), clean up
@@ -24,8 +37,7 @@ fi
 if sudo test -f "$NOPASSWD_FILE"; then
   if [[ $1 ]]; then
     sudo systemctl stop "${TIMER_NAME}.timer" 2>/dev/null
-    sudo systemd-run --on-active=${MINUTES}m --timer-property=AccuracySec=1s --unit="$TIMER_NAME" \
-      rm "$NOPASSWD_FILE"
+    arm_expiry || exit 1
     echo "Passwordless sudo timer updated. It will now automatically disable in ${MINUTES} minutes."
   else
     sudo rm "$NOPASSWD_FILE"
@@ -48,12 +60,11 @@ else
   if gum confirm "Enable passwordless sudo for ${MINUTES} minutes? This is a significant security risk!"; then
     echo "${USER} ALL=(ALL) NOPASSWD: ALL" | sudo tee "$NOPASSWD_FILE" > /dev/null
     sudo chmod 440 "$NOPASSWD_FILE"
-    sudo systemd-run --on-active=${MINUTES}m --timer-property=AccuracySec=1s --unit="$TIMER_NAME" \
-      rm "$NOPASSWD_FILE"
+    arm_expiry || exit 1
 
     echo ""
     echo "Passwordless sudo has been ENABLED. It will automatically disable in ${MINUTES} minutes."
-    echo "Note: if you restart before then, run omarchy-sudo-passwordless again to disable it."
+    echo "A restart removes the passwordless sudo rule as well."
   else
     echo "Aborted. No changes made."
   fi