Anchor heading
The AnchorHeading component emulates the behaviour of the rehype-slug ↗ and rehype-autolink-headings ↗ plugins.
It adds an id based on the output of github-slugger ↗ to the heading, as well as adding a button to copy a link to that particular heading.
This is only required when writing headings yourself inside components, Markdown (including partials) will have this applied via the aforementioned rehype plugins.