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## Summary of the Pull Request
Add the ability to toggle a pane's split direction
- Switch from horizontal to vertical split (and vice versa)
- Propogate new borders through to children.
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## References
#10665
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## PR Checklist
* [x] Closes#10665
* [x] CLA signed. If not, go over [here](https://cla.opensource.microsoft.com/microsoft/Terminal) and sign the CLA
* [ ] Tests added/passed
* [ ] Documentation updated. If checked, please file a pull request on [our docs repo](https://github.com/MicrosoftDocs/terminal) and link it here: #xxx
* [x] Schema updated.
* [ ] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan. Issue number where discussion took place: #xxx
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## Detailed Description of the Pull Request / Additional comments
<!-- Describe how you validated the behavior. Add automated tests wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed
Ran terminal, created multiple panes in different orientations, ran command through command palate and verified that they displayed properly in the new orientation.
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