One thing I discovered raising chicks is that as long as the chicks have a hot area and a cold area they can move about find a comfortable temperature. So you don't really have to worry about cooking the chicks by not having the heat lamp set up just right.

Cats love warmth so much though, I have seen (and smelled) cats singe their fur by laying too close to the fireplace. So maybe a cat is more at risk of cooking if the heater sticks on.

Anyways cool project. The concept of fault tolerant automated systems, or even ones that can self-heal is very appealing.