fix(stop): clear stale restart-request lock + warn on failed player query

Addresses Copilot review feedback on #4595:
- command_restart.sh: clear the *-restart-request.lock once a restart
  actually proceeds. Previously the lock was only written when postponing
  and never removed, so every subsequent monitor run would see the stale
  lock and trigger a repeat restart indefinitely. Fixed and verified against
  a live server: postponed restart -> monitor executes it and clears the
  lock -> a second monitor run no longer restarts.
- check_players_online.sh: if the gamedig query fails for every configured
  IP (e.g. gamedig/jq missing), playersonline now still fails open (so a
  broken query can't permanently block stop/restart) but prints a clear
  warning that the safety check could not run, instead of silently
  behaving as if the server were empty.

lgsm/modules/check_players_online.sh

@@ -12,14 +12,23 @@ moduleselfname="$(basename "$(readlink -f "${BASH_SOURCE[0]}")")"
 playersonline=""
 if [ "${stoponlyifnoplayers}" == "on" ]; then
 	if [ "${querymode}" == "2" ] || [ "${querymode}" == "3" ]; then
+		querysucceeded="0"
 		for queryip in "${queryips[@]}"; do
 			query_gamedig.sh
 			if [ "${querystatus}" == "0" ]; then
+				querysucceeded="1"
 				if [ -n "${gdplayers}" ] && [ "${gdplayers}" -ne 0 ]; then
 					playersonline="${gdplayers}"
 					break
 				fi
 			fi
 		done
+		# The query failed for every configured IP, so the player count could not be
+		# determined. Fail open (proceed as if empty) rather than block the server
+		# indefinitely, but warn clearly since the safety check did not actually run.
+		if [ "${querysucceeded}" == "0" ]; then
+			fn_print_warn_nl "Unable to determine player count: stoponlyifnoplayers check skipped"
+			fn_script_log_warn "Unable to determine player count via gamedig: stoponlyifnoplayers check skipped"
+		fi
 	fi
 fi

lgsm/modules/command_restart.sh

@@ -20,6 +20,9 @@ if [ -n "${playersonline}" ]; then
 	date '+%s' > "${lockdir:?}/${selfname}-restart-request.lock"
 	core_exit.sh
 fi
+# Clear any pending restart request now that the restart is actually proceeding,
+# so a stale lock doesn't trigger a repeat restart on the next monitor run.
+rm -f "${lockdir:?}/${selfname}-restart-request.lock"
 exitbypass=1
 command_stop.sh
 command_start.sh