Caravans can get medical help from friendly factions

[AnActualDuck]

I just had a person in my caravan come down with the plague when I realized I had no competent doctors in the group. I was, however, right next to a allied colony. I think it'd make sense if you could stop at an allied colony and request medical aid and receive treatment to any sick or wounded. A fee could be associated with it, the menu could pop up with each colonist and a calculated amount of silver to treat them based on their ailments.