[Feature] Readme / Markdown File Outline Navigation

[Forger125]

A feature recently introduced in GitHub is the ability to navigate README.md files using a header-based outline tab (see images below). This seems like a nice quality-of-life feature. Also, building on this possibility, would it be possible to add this capability for all Markdown files (e.g. be able to use outline navigation within the file previewer)?

Also, just want to say a huge thank you to all the developers and community that makes Gitea possible - you all rock! 😄

[silverwind]

There were already attempts to add auto-generated TOCs, so maybe work on this a feature can build on existing work. Hiding it behind a hamburger menu does seem like a good idea to me. That way we don't alter the original markdown rendering.