[codex] Disable unsafe Pylint extension loading

[adamtheturtle]

Summary

Adds MASTER.unsafe-load-any-extension = false to the Pylint configuration in pyproject.toml.

Impact

This keeps Pylint from loading arbitrary C extensions while preserving the existing configured plugin list.

Validation

• python3.12 -c 'import pathlib, tomllib; tomllib.loads(pathlib.Path("pyproject.toml").read_text())'
• Commit hooks: check toml, pyproject-fmt, and other configured pre-commit checks passed
• Push hooks: mypy, check-manifest, pyright, ty, and pyrefly passed