> The driver said she was using Autopilot, that an OTA update had had a problem earlier in the day, and that she had actually had the same kind of collision on Autopilot previously!
Autopilot might be an absolute dumpster fire, but what you are describing is similar to an adaptive cruise control failure and the liability is still with the driver. She rear ended you while you were at a red light, make sure that her insurance pays and that's it. If she wishes to sue Tesla she can obviously do so.