Style guide automation

[vinckr]

Preflight checklist

• [x] I could not find a solution in the existing issues, docs, nor discussions.
• [x] I agree to follow this project's Code of Conduct.
• [x] I have read and am following this repository's Contribution Guidelines.
• [x] I have joined the Ory Community Slack.
• [x] I am signed up to the Ory Security Patch Newsletter.

Describe your problem

style guide is not automated

Describe your ideal solution

• bring back https://github.com/ory/docs/pull/775 with some reduced/custom style set, review our markdownlint rules, and generally also review and update the README style guide

Workarounds or alternatives

no automation