Document standalone version

[Josehower]

in theory, we don't need to use upleveled-eslint-config in order for this stylelint to work.

We can install stylelint + stylelint-config-upleveled and use this config file

// stylelint.config.cjs

/** @type { import('stylelint').Config } */
const config = {
  extends: ['stylelint-config-upleveled'],
};

module.exports = config;

we can add this to the documentation later