math: quaternion to rotation matrix conversion

[nothke]

There seems to be no quaternion rotation to matrix conversion in math. Mat4x4 has rotateX, rotateY, rotateZ functions, but no rotate that would take a quaternion. Is it just missing or is there another way to get one to perform a translation, rotation, scale (TRS) transformation on a matrix?

[emidoots]

Just missing yep.

We just need an implementation that is proven correct and follows Mach's chosen math conventions, not copy-pasted from a different codebase, etc.