[Idea] Let advanced users turn off the auto-updating

Our more advanced users would like to be able to turn off code auto-update, particularly for their long programs. That way they can write a lot of code and not get as distracted along the way by Oh Noes or experience any lag.

This would be pretty easy to implement, the hard part would be how to surface it and when to surface it (like only via keyboard shortcuts, in a menu for advanced folks, etc).

No files, tests, or entry points are named. First locate the code that triggers automatic updates and review how editor controls or keyboard shortcuts are surfaced; done means advanced users can reliably disable auto-updating, avoid lag while writing long programs, and re-enable it when needed.

Written by the indexing model from the issue text.