[Suggestion] Filter NPC stations from !cleanup commands

[XeroCreator]

Requesting to filter out NPC stations from !cleanup commands to prevent accidental deletion of them. You can't delete them from entity list unless you break up the station in-game manually. I ... dumbly deleted around half of the stations because of my normal cleanup hitting at the end of a month, and It caused over half the npc stations to be deleted. Not sure if you could filter them, but figured i'd leave a suggestion for it.