What is the name of a footprint that is designed to let you cut the trace between two nets?
Sometimes called a "Solder-Short" pattern. To create it you could use two half-moon shaped pads placed very close together, be sure to keep solder mask off the junction area. Usually the idea here is if you need the two signals shorted you then put down a solder blob covering both pad ends. With this method you start out with an open.

A way to create it and still keep the net connection would be to use an oval shaped pad with an oversized (non-plated) drill hole. You then run the two traces to the pad from opposite ends. The drilling of the over-sized hole physically cuts the pad in two. Re-solder the connection if needed later on.