Gate EdgeEnv preservation in agent reports

[hyeokjun32]

Summary

• add a committed EdgeEnv runs-show fixture for Runtime operation preservation
• add a local smoke gate for the Lab Agent Runtime EdgeEnv preservation section
• document the smoke and fixture in README/portfolio docs

Tests

• python3 -m json.tool examples/agent_runtime/edgeenv_run_show_runtime_operation.json >/tmp/edgeenv_run_show_fixture_check.json
• bash scripts/smoke_agent_runtime_edgeenv_preservation.sh --output-dir /tmp/inferedgelab_agent_runtime_edgeenv_preservation_smoke
• poetry run python3 -m pytest -q tests/test_agent_runtime_edgeenv_preservation_smoke_script.py tests/test_agent_runtime_report.py
• poetry run python3 -m pytest -q
• poetry run inferedgelab portfolio-demo-check