Type annotations

[boombard]

Hi 👋 great library. Is there any existing work to add type annotations to pymoo? If not I'd be happy to contribute. Perhaps just starting with core and iterating on the rest of the library?

[blankjul]

Happy to look at a PR. Probably good to split it up into multiple.
You might even be able to use an LLM to do it for some files rather quickly (but would need to be checked carefully)

And yes when starting the framework I have not used any type annotations which is very tempting in Python as well.