Another Experiment To Make Unsafe Rust Safer: Preventing UB In MaybeUninit With Compile Time Error

Yeah, I'm still thinking about this :]. The last one was about aliasing UB, refined from previous feedback. Could you recheck it?

For now, I'm also trying to catch compile time errors for other UB sources, like std::ptr::copy_nonoverlapping aka memcpy, std::mem::transmute, etc just to collect them first. If that goes well, I'll introduce it

What are some other sources of UB in unsafe Rust? I want to experiment with more common UB mistakes, but I'm not sure what else is out there