dokytree/samples/doc_v1/doc/structure/05_file.name.ext/_index.01.md

You can store additionnal files related to the yaml file.
As exemple, with _index.yaml, you can add _index.01.md or _index.01.svg.
You can use the same method with item.yaml files.
Thoses files can be added as headfile, file or footfiles just using 01.md or 01.svg.

Supported extentions

Text: txt adoc
Parsed: md html pug
Images: svg png jpg jpeg gif bmp