Fix CodeQL registry validation temp write

[saagpatel]

Summary

• add an in-memory registry markdown parser entrypoint while preserving parse_registry(path)
• validate generated registry markdown without writing the generated content to a temporary file
• add regression coverage that validate_registry_markdown does not create the compatibility temp path

Security

• Targets CodeQL alert #466: py/clear-text-storage-sensitive-data at src/github_repo_auditor/portfolio_truth_validate.py:2328
• Removes the temp-file sink that stored generated registry Markdown during validation

Verification

• PYTHONPATH=src /opt/homebrew/bin/pytest tests/test_registry_parser.py tests/test_portfolio_truth.py::test_rendered_registry_round_trips_through_parser tests/test_portfolio_truth.py::test_registry_validation_does_not_write_temp_markdown tests/test_portfolio_truth.py::test_registry_render_surfaces_security_and_round_trips -q
• PYTHONPATH=src /opt/homebrew/bin/pytest tests/test_portfolio_truth.py -q
• uv run --no-sync ruff check .
• git diff --check

Notes

• CodeQL/provider closure is not claimed until GitHub checks run on this PR and the alert is fixed or dismissed through the provider.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-02T08:07:13.268031Z	393222f	PR opened

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