This contains the main changes to the extensions crate from #20049. The
primary goal here is removing dependencies that we can't include on the
remote.
Release Notes:
- N/A
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Co-authored-by: Mikayla <mikayla@zed.dev>
Co-authored-by: Marshall Bowers <elliott.codes@gmail.com>
Co-authored-by: Marshall <marshall@zed.dev>