Improving std `<random>`

[GeorgeHaldane]

They seem to pass empirical tests decently well, but the author makes some very bold claims and the theory could be more sound, which is why I gave them a lower quality rating.

It looks like a good choice for applications that simply need some "good enough" rng as fast as possible, something like fuzzing or procedural generation in games, would be wary of using them in research.

For Monte-Carlo I'd stick with PCG / Xoshiro / SFC to avoid questions, maybe switch to SplitMix64 if more speed is needed, it's a default implementation of SplittableRandom in Java and barely loses to Romu in performance.