[WIP] Configure instructions for Copilot in repository

[Copilot]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>✨ Set up Copilot instructions</issue_title>
<issue_description>Configure instructions for this repository as documented in Best practices for Copilot coding agent in your repository.

</issue_description>

Comments on the Issue (you are @copilot in this section)

Fixes #227

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✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

[joe10832]

@copilot