zombieCraig/UDSim ? reverse-engineered prompt

Build me a desktop app called UDSim that can act like a fake car control module on a CAN bus. It should have a simple graphical interface where I can see learned modules, switch between learning, simulation, and attack modes, and save what it learns into a config file I can reuse later.

I want it to listen on a CAN interface, pick up UDS traffic, and learn the requests and responses from live traffic or from a candump log. Then it should let me simulate those modules so diagnostic tools still think they are talking to a real vehicle. It should also have a basic fuzzing mode for testing diagnostic tools, with options to keep the VIN the same or randomize response data a little.

Please make it work with a plain text config format, support fullscreen, logging, and show module cards in the UI. If you need current docs for CAN or UDS handling, look them up online as you build it.