Adds comparisons to langchain

[skrawcz]

This I think shows a few things well.
Langchain is obviously smaller, but
it's a lot less flexible and hides a lot.

Changes

• adds to docs
• adds to examples

How I tested this

• ran things locally

Notes

• I had to update configuration for pre-commit because we need the code to be skinny to display well side by side.

Checklist

• PR has an informative and human-readable title (this will be pulled into the release notes)
• Changes are limited to a single goal (no scope creep)
• Code passed the pre-commit check & code is left cleaner/nicer than when first encountered.
• Any change in functionality is tested
• New functions are documented (with a description, list of inputs, and expected output)
• Placeholder code is flagged / future TODOs are captured in comments
• Project documentation has been updated if adding/changing functionality.