Find a way to incorporate the 2D diagram into the section about bootstrapping

[jyn514]

@mark-i-m came up with a really great diagram about bootstrapping:

Unfortunately, the diagram has turned out to be really controversial: some people love it, other people think it just makes things more confusing.

I do not have the energy to work out a consensus here, but since so many people have found it helpful, it would be great to incorporate it into the docs somehow.

[jyn514]

I am going to close this; I think a diagram for the transition from --stage to --sysroot (https://jyn.dev/2023/01/12/Bootstrapping-Rust-in-2023.html) will be helpful, but it won't be exactly the same as this diagram.