docs: add readmes to the examples

[huncholane]

No description provided.

[epage]

I feel like this should instead be a combination of

• top-level doc comment (the what, recommendations for playing with it)
• code cleanup (the "how it works")
• maybe a table-of-contents in the main library like we do with clap, see clap's cookbook (key concepts but re-framed less around the implementation)

[huncholane]

I feel like this should instead be a combination of

* top-level doc comment (the what, recommendations for playing with it)

* code cleanup (the "how it works")

* maybe a table-of-contents in the main library like we do with clap, see [clap's cookbook](https://docs.rs/clap/latest/clap/_cookbook/index.html) (key concepts but re-framed less around the implementation)

I got the inspiration from a python library pocketflow. It's really nice to have a readme inside each individual example. Personally, I prefer to look at github over rust docs, so this is a highly opinionated request and understand if it goes against your vision.

[epage]

Interesting that you prefer github. Generally, the feedback I've gotten is

• People want to look in one place
• It is confusing when looking at one version of an API to then get examples in a different version

I think we can also offer a better presentation in rustdoc and would still prefer doc comments.

I'm also tempted to move most of these examples to being a file, rather than a directory.