🚀 Feature: Use cspell as an ESLint plugin

[JoshuaKGoldberg]

Bug Report Checklist

• I have tried restarting my IDE and the issue persists.
• I have pulled the latest main branch of the repository.
• I have searched for related issues and found none that matched my issue.

Overview

Splitting out of #834: right now, spell checking is done directly through cspell. But it'd be great to move it into the ESLint to work alongside other linting bits. https://www.npmjs.com/package/@cspell/eslint-plugin

Additional Info

This is not a good first issue - I'm not 100% confident that this is the right way to go. I've never tried spell checking through an ESLint plugin. I'll take a PR, but no guarantees I'll end up liking it. Contributor beware!

[JoshuaKGoldberg]

Unfortunately, this doesn't do away with the need for some kind of CSpell configuration. I'm going to wontfix this. Ah well!