Seed user guide from existing google doc

https://docs.google.com/document/d/1xb5VW09DgFeNxyMCVYg_uo_torqCBqEE0Uxzl_11OtA/edit?usp=sharing has a section at the bottom with some useful stuff to copy over.

We can start more sections under https://a-b-street.github.io/docs//user/index.html

The issue references a Google Doc with content to copy. Start by reviewing the linked document and the existing user guide structure at https://a-b-street.github.io/docs//user/index.html. Determine where the new sections fit, then add the content to the appropriate Markdown files in the repository. Verify the changes build correctly to update the live site.

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