Include external guidance on data preparation

[larsvilhuber]

Curtin, L., Herzog, J., Richardson, J., Prabhakaran Nair Sheelakumari, L., & Steltenpohl, C. N. (2025). Best Practices for Data Submission in Generalist Repositories: A Checklist. Zenodo. https://doi.org/10.5281/zenodo.14278907

https://datadryad.org/docs/HumanSubjectsData.pdf (with BIG caveats...)