Implement a slugify helper for this Python utility library: src/slugify.py with a function slugify(text: str) -> str (lowercase; spaces and punctuation collapsed to single hyphens; leading/trailing hyphens stripped; unicode letters transliterated to ascii where trivially possible, otherwise dropped), plus unit tests in tests/test_slugify.py runnable with `python3 -m unittest discover -s tests`. Run the tests until green and commit your work. This repo uses flow-next for task tracking - follow the repo instructions and track this piece of work start to finish exactly as the project conventions require, including recording completion evidence.
