## Summary

What does this PR change and why?

## Test plan

- [ ] `cd rust && cargo test`
- [ ] `cd rust && cargo clippy --all-targets --all-features -- -D warnings`
- [ ] `cd rust && cargo fmt --check`
- [ ] If cookbook/packages changed: relevant `npm test` / build steps

## Notes for reviewers

- Risk areas / edge cases:
- Backwards compatibility:
- Docs updated (links/files):

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