Format Rust sources to satisfy CI (#57)

Apply rustfmt across the CLI, API module, benchmarks, and smoke tests to
resolve formatting failures in PR #48 without intended behavior changes.

Validation: `cargo fmt --all -- --check` passes.

[View coding
task](https://app.coderabbit.ai/code/tasks/92ffd79b-21b5-4700-8057-44c3475a98dd?source=coding_agent_github_pr_description)

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Signed-off-by: Jonathan D.A. Jewell <6759885+hyperpolymath@users.noreply.github.com>
Co-authored-by: Jonathan D.A. Jewell <6759885+hyperpolymath@users.noreply.github.com>
Co-authored-by: codacy-production[bot] <61871480+codacy-production[bot]@users.noreply.github.com>
Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>
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Author: 4 people