feat: prepare Jetson evidence contract

[hyeokjun32]

Summary

• Added Runtime CLI fields for Jetson evidence context: power mode, jetson_clocks, and tegrastats log path.
• Added tegrastats summary export under jetson_evidence for Lab-compatible Runtime JSON.
• Documented the Jetson Evidence Track preparation path before actual Jetson smoke testing.

Validation

• bash scripts/smoke_default.sh
• /opt/anaconda3/bin/python -m pytest tests/test_lab_result_schema.py -q
• /opt/anaconda3/bin/python -m pytest tests/test_manifest_compare_identity.py -q
• /opt/anaconda3/bin/python -m pytest tests -q

Notes

• No actual Jetson smoke result was generated in this step.
• This prepares the Runtime contract immediately before Jetson Orin Nano validation.