Persist Folded/Unfolded code sections across sessions

[asalvi0]

Check for existing issues

• [X] Completed

Describe the feature

Description: Currently, the editor resets all code sections to their unfolded state upon application restart or file reopening.

Proposal: To improve usability and streamline workflow, it would be nice for Zed to remember the folded/unfolded state of code sections across sessions. This way, users can pick up exactly where they left off, enhancing productivity and focus when navigating through files with numerous sections.

If applicable, add mockups / screenshots to help present your vision of the feature

No response