This replaces standard with neostandard and:

• adds the result of running a npx eslint --fix
• removes no longer supported /* eslint-env mocha */ and replaces it with env: ['mocha'] in the neostandard config (it adds it globally, but I think that's okay for this project, a more deluxe solution would be to instead do: https://github.com/voxpelli/eslint-config/blob/main/base-configs/mocha.js)
• adds a neostandard badge, I opted for the one without the neostandard colors 😜

Also:

• adds rimraf, because there's a dependency on it that worked when standard made it be included
• adds knip to help avoid the above
• cleaned up stuff and refactored some stuff to help knip
• added installed-check to ensure that the engine range is good