When reading from .md files, split markdown cells on titles to help with collapsing

[meditans]

Description

Say one has this structure on a markdown representation of a notebook:

# Title of the thing
Description of what the file is trying to accomplish.
Ullam earum consectetur assumenda vero omnis qui perspiciatis eveniet. Quibusdam temporibus aut itaque quisquam iste rerum. Ut vero architecto est. Itaque enim porro error. Rerum non incidunt qui numquam perferendis sed eos vero. 

## First section

this is read by marimo as a single markdown cell, and that means that one can only opt to collapse it to Title of the thing. It would be nice instead if I could collapse the First section alone.

Suggested solution

When you read from markdown file, consider splitting the content in cell based on headlines.

Alternative

No response

Additional context

No response

[dmadisetti]

Markdown cells can be split with an empty html tag
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Hmm, I think splitting on headings is little opinionated