Persist undo history across restarts

[N8th8n8el]

Check for existing issues

• [X] Completed

Describe the feature

Title says it all. I'm experiencing this issue at least once a day https://github.com/zed-industries/zed/issues/5951 which I guess is the main reason for wanting this feature. But even outside of that I can imagine this being useful.

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

No response