erincatto/box3d ? reverse-engineered prompt

Build me a 3D physics engine for games in portable C17, with a clean public API and a small samples app so I can see it working right away.

I want solid collision handling for things like convex hulls, capsules, spheres, triangle meshes, and height fields, plus ray casts, shape casts, overlap checks, sensors, and contact events. It should also support rigid bodies with a good solver, sleeping, joints like revolute, prismatic, distance, motor, weld, and wheel, and basic forces, limits, springs, and friction. Please make it cross platform and easy to build with CMake, with a simple way to run the demo app on Windows, Linux, and macOS. If you need to, look up current docs online and follow the patterns already used in the repo. Also include a minimal hello world style example and keep the code organized so it can be used as a library in another game project.