Revert "gpui: Do not render ligatures between different styled text runs (#37175) (#37382)

This reverts commit 62083fe7963dd5bed4579bb12abac1b7800cdbaa.

We're reverting this as it causes layout shift when typing/selecting
with ligatures:


https://github.com/user-attachments/assets/80b78909-62f5-404f-8cca-3535c5594ceb

Release Notes:

- Reverted #37175
ad3ddd381dMarshall Bowers committed on 9/2/2025, 4:18:49 PM· committed by GitHubparent7e3fbeb
3 files changedLine totals unavailable