feat: surface runtime timeout evidence in agent report

[hyeokjun32]

Summary

• Added Lab decision policy handling for Runtime timeout observation evidence.
• Included runtime timeout policy, budget, and observed status in Agent Runtime Reliability reports.
• Added tests covering review-required decisions from Runtime timeout observations.

Validation

• poetry run python3 -m pytest tests/test_agent_runtime_report.py -q
• poetry run python3 -m pytest -q
• git diff --check

Notes

• This is additive report/decision context only.
• Runtime timeout observation means a configured latency threshold was breached; it does not claim production request cancellation.
• Lab remains the final deployment decision owner.