Launching an application from the launchd root context as the console user - https://jamfnation.jamfsoftware.com/discussion.html?id=4117

launch.sh

#!/bin/bash
declare -x UserName="$(/usr/bin/who | /usr/bin/awk '/console/{print $1;exit}')"
echo "Derived Console username: $UserName"
declare -x LoginWindowPID="$(/bin/ps -axww | /usr/bin/grep loginwindo[w] | /usr/bin/awk '/console/{print $1;exit}')"
echo "Found PID: $LoginWindowPID"
/bin/launchctl bsexec "${LoginWindowPID:?}" /usr/bin/sudo -u "$UserName" /usr/bin/open /Applications/Calculator.app