idea: write markdown, get a more-or-less readable with categories and search
because no one wants to deal with wikis (or just use fd & rg locally, I guess).
Add docs to `content/`; all subdirs of that need a _index.md file that defines
the theme. Categories are just strings and can be defined ad-hoc; the search
goes through all files in `content/` and subdirs based on a search index built
by zola when building the site.
