move new content from main book to supplementary

Over time, I have added ~20 pages of new content, which MIT Press does not want.
So I have moved the sections below to the online supplement,
so length is closer to 1351 pages of the 2023-jan-22 version (first printing)
(Diff created using ChatGPT 5.1)

https://chatgpt.com/share/693e4ddc-7bf4-8005-912c-037f5fff23d4