nicolejrkim/DTMR ? reverse-engineered prompt

Build me a Python project that retargets human motion onto legged robots and keeps the timing flexible so the robot can slow down or speed up parts of the motion when needed. I want it to run on a GPU with MuJoCo Warp, take in a motion clip that has already been retargeted, and track it with sampling based MPC while showing a live robot simulation.

Please include support for a few humanoid robot setups, a simple way to add more later, and command line tools to run a tracking job, render the result to an mp4, and report basic tracking scores. It should also come with a couple of ready to run demo scripts so I can try a sample style clip and a sprint tutorial right away.

If anything depends on current library or simulator docs, look them up online and use the recommended setup. Keep it easy to install and make the main workflow work from one or two commands.