- Split _alarm.py (1059 lines) into _alarm.py + _audio.py + _challenges.py
- Split test files (1305 / 725 lines) into 6 files, all under 500 lines
- Replace random.* with secrets.* (S311); fix RUF001, SIM117, E501 ruff errors
- Rewrite pytest_changed_packages.py to always run all packages with global
--cov python_pkg coverage (100% branch coverage enforced across whole tree)
- Add DISMISS_ROUNDS_REQUIRED=2 and DISMISS_FLASH_SECONDS=4 to _constants.py
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>