WIP: Make espresso pip-installable

[jhossbach]

Closes #4222

scikit-build is used to build espresso with CMake and install espressond in the site-packages directory.
This should also resolve the issue with paths in virtual environments without needing to add a .pth file (#4872) and should make espresso pretty easy to install in any environment.

Things I haven't touched:

• Adding metadata to the setup.py, such as the license or description.
• Building should happen in parralel with ninja but I am not sure if this was the case on my PC, so parallel building should be checked.
• Documentation
• of course updating the CI etc.

[PythonFZ]

Are there any updates on this? I see that the package compiles given these changes but either installing it via uv pip install . or editable via uv add / uv sync gives me an import error espressomd not found.