Back in the day (<=0.17) there was a mod called Lockable Doors ( https://github.com/khell/RimworldLockableDoors ) which would let you lock doors to restrict who is allowed entry.
I just recompiled it against 1.0 (after adding a single unimplemented method and updating the XML Defs).
This old mod would actually prevent colonists with mental breaks from going through the doors, as well as prevent prisoners from slipping out (without breaking down the door first). It's a little fiddly, and I don't like that you can magically lock a door without a colonist needing to visit the door, but it's solid and actually works. (Of note, the interface and idea behind the Locks mod I think is better, but colonists suffering mental breaks get to go through all doors).
Anyway, since the license on the mod is permissive, I'm making the patched, compiled version available for download here: https://lp-programming.com/LockableDoors.zip
P.S. In B18, there was another mod that provided flickable locking, with a locked door unpassable by anyone, but I cannot remember which it was. If anyone has the name, I'd appreciate a mention, I may see if I can get it running on 1.0.
I just recompiled it against 1.0 (after adding a single unimplemented method and updating the XML Defs).
This old mod would actually prevent colonists with mental breaks from going through the doors, as well as prevent prisoners from slipping out (without breaking down the door first). It's a little fiddly, and I don't like that you can magically lock a door without a colonist needing to visit the door, but it's solid and actually works. (Of note, the interface and idea behind the Locks mod I think is better, but colonists suffering mental breaks get to go through all doors).
Anyway, since the license on the mod is permissive, I'm making the patched, compiled version available for download here: https://lp-programming.com/LockableDoors.zip
P.S. In B18, there was another mod that provided flickable locking, with a locked door unpassable by anyone, but I cannot remember which it was. If anyone has the name, I'd appreciate a mention, I may see if I can get it running on 1.0.