Harden Runtime telemetry history seed contract

[hyeokjun32]

Summary

• strengthen Runtime schema and smoke assertions for runtime_telemetry.history_seed
• verify replay_scope, source result schema, evidence role, power mode, telemetry source, and replay point mirrors
• document that EdgeEnv preserves the seed while Lab owns deployment decision reporting

Tests

• python3 tests/test_lab_result_schema.py && python3 tests/test_agent_runtime_result_contract.py
• bash scripts/smoke_default.sh
• python3 tests/test_manifest_compare_identity.py
• python3 -m unittest discover -s tests -p 'test_*.py'
• git diff --check