Add first integration queue round-trip test

[psychocoderHPC]

Split from local commit 315e8f3def4c3a502ef9966ad66f0e252f260f4e.

Base branch: pr-add-getconstmdspan-coverage.

[coderabbitai]

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch pr-add-queue-buffer-roundtrip-test

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