The documentation is split across two subfolders, `source` and `assets`. The folder `source`
contains the static source files that make up the user guide, which are mostly markdown files and
the snippets of code. The folder `assets` contains (dynamically generated) assets used by those
files, including data files for the snippets and images with plots or diagrams.

Do _not_ merge the two folders together. In
[PR #18773](https://github.com/pola-rs/polars/pull/18773) we introduced this split to fix the MkDocs
server live reloading. If everything is in one folder `docs`, the MkDocs server will watch the
folder `docs`. When you make one change the MkDocs server live reloads and rebuilds the docs. This
triggers scripts that build asset files, which change the folder `docs`, leading to an infinite
reloading loop.
