Fix vim macros duplicating inserted characters

[AshtonCoates]

📝 Summary

Fixes issue with CodeMirror where vim macros would duplicate characters typed in insert mode.
Closes #8469

🔍 Description of Changes

I believe that the handleKey method is called once per editor instance. Thus if we have 3 cells (editors) and enter insert mode, each of the 3 editors insert each character typed.
By removing the relevant code block I was able to fix this behavior and have not observed any side-effects.
Added comment to explain logic flow for this section
I did not add a test for this issue, but all existing other tests are passing after the change.

📋 Checklist

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• For large changes, or changes that affect the public API: this change was discussed or approved through an issue, on Discord, or the community discussions (Please provide a link if applicable).
• Tests have been added for the changes made.
• Documentation has been updated where applicable, including docstrings for API changes.
• Pull request title is a good summary of the changes - it will be used in the release notes.

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Project	Deployment	Actions	Updated (UTC)
marimo-docs	Ready	Preview, Comment	Mar 2, 2026 11:42pm

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[AshtonCoates]

I have read the CLA Document and I hereby sign the CLA

[AshtonCoates]

recheck

[manzt]

Thanks for putting this up. I can see that our handleKey approach breaks macros.

However, I believe removing this block disables insert-mode syncing across cells, which we don't want to regress. We likely need a more direct way to enter insert mode on sibling editors (similar to how the "normal" case calls Vim.exitInsertMode directly).

[AshtonCoates]

Thanks for the feedback, I hadn’t considered the syncing issue. I’m still getting familiar with the codebase and frontend framework, so I appreciate the clarification.

I’ll take another look and work on a more robust approach

[AshtonCoates]

Just realized last commit included a regression, I'll fix soon

[AshtonCoates]

@manzt I implemented a workaround by essentially skipping the mode change broadcast when we're recording or playing a macro. This shouldn't break synchronization because a macro should take place within one cell anyways, and should always start and end in normal mode.