Add initial version of python bindings

[sovrasov]

What does this PR do?

• uses nanobind to construct the bindings
• covers classification
• bindings are optional to avoid unnecessary side-effects in other projects that use model_api/cpp

Fixes # (issue)

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
• Did you make sure to update the documentation with your changes?
• Did you write any new necessary tests?

[sovrasov]

Had to do weird stuff in cpp CI workflows, because g++11 throws unexpected warnings on nanobind code, while warning compile flags are global in the existing CMake script.