Remove debugpy as dependency?

debugpy is quite a heavy dependency, before it was a build dependency, but now it's standard:

It shows up as 28MB on disk
```
28M /Users/maartenbreddels/venvs/solara-size1/lib/python3.9/site-packages/debugpy
```

On pypi https://pypi.org/project/debugpy/#files it's ~5mb.

I'm not sure everyone needs a debugger, and in times of pyodide/pyscript, size matters :)

I think the code is already prepared for it (try block around the import).