Ensure eval smoke uses normalized output bundle

[RNA4219]

Summary

• allow eval_smoke.sh to optionally preserve its working directory for inspection
• propagate normalized text into the generated JSONL files without ASCII escaping
• extend the smoke test to assert the preserved bundle contains the normalized stub output

Testing

• pytest tests/scripts/quality/test_eval_smoke.py

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https://chatgpt.com/codex/tasks/task_e_6907403174288321af3c016459d312dd