Consider making use of the code annotation features of Quarto

[Bergam0t]

I didn't find out about the code annotation features of Quarto until very late in this process of writing the first draft.

https://quarto.org/docs/authoring/code-annotation.html

I think this could really enhance the code examples, so may be worth tweaking some or all examples.

Only concern is that this may mean we are inclined to remove comments from copyable code examples, which may make it harder for people to follow the logic when reusing.