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## Summary

<!-- What does this PR do, and why? Link the motivating issue. -->

Closes #

## Changes

<!-- Bullet the notable changes. Call out any new public API surface. -->

-

## API spec impact

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This SDK tracks a pinned Exchange API spec version (`.api-version`).
Check the box that applies.
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- [ ] No change to the targeted API spec version.
- [ ] Bumps `.api-version` (and the README spec table) to a new release — the `spec-drift` check enforces this stays in sync.

## Checklist

- [ ] `cargo fmt --all` is clean (`fmt`).
- [ ] `cargo clippy --all-targets --all-features -- -D warnings` passes (`clippy`).
- [ ] `cargo test --all-features` passes (`test`).
- [ ] `cargo doc --no-deps --all-features` builds without warnings (`doc`).
- [ ] New/changed public items have rustdoc.
- [ ] Dependency or license changes considered against `deny.toml` (`cargo-deny`).

## Notes for reviewers

<!-- Anything reviewers should focus on, risks, or follow-ups. -->
