sapolayot/pose-weight ? reverse-engineered prompt

Build me a small JavaScript app called pose weight that helps a user work with body pose data and see a clear result on screen. I want it to feel simple and polished, with a main page where someone can try it out, see feedback right away, and understand what the app is doing without needing instructions. Use the existing project setup, keep it lightweight, and make sure it runs cleanly from the start.

If there’s any choice about the best library or approach for handling pose data, use something current and practical, and look up the latest docs online if you need to. Please also make the basic developer setup easy, so I can install it, run it locally, and understand where the important pieces are without digging too much.