feat: `[[example]]` targets

[Autoparallel]

We have a LOT of different tools now. A LOT of tests. However, we need some example bins!

What would be great is some simple binaries for our different primitives that allow for things like:

• user input
• pretty logging/tracing to show the steps of computation
• string multiple primitives together into more of a "protocol" and repeat above

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• [x] #109
  • uses a hash function and a stream cipher to do message authentication

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TODO: Coming back to this to add more

[Autoparallel]

Another option is to make a ronkathon-cli crate that exposes some interaction for the various things! I am good with either approach!