Need README Page for Datasets

After getting feedback on the [jail hub](https://jails.ics.uci.edu/dashboard/about), the need for dataset documentation was brought up by Social Science researchers. Adding a README page will make datasets and workflows more accessible and understandable for users trying to view and edit existing workflows. The README will use a lightweight code editor and markdown renderer, and will be similar to [Kaggle](https://www.kaggle.com/datasets/yashmotiani/blinkit-marketing-and-customer-powerbi-dashbord) dataset README.

[Design document](https://docs.google.com/document/d/1b2QvpJcUvEenRUnz7WnuuqcJqL1iLMFjWYav60MawQk/edit?usp=sharing)

Start with the linked design document and the existing dataset and workflow viewing experience described in the issue. Confirm the intended README layout, then implement the dataset page with a lightweight editor and Markdown renderer; done means users can view and edit dataset README content alongside existing workflows.

Written by the indexing model from the issue text.