Stub file contains `typing.Any` type hint for many signatures

[smartgoo]

The generated stub file kaspa.pyi contains typing.Any type hint for many function signatures. For example:

def disconnect(self) -> typing.Any:
        ...

def start(self) -> typing.Any:
        ...

The API Reference pages of the docs site is built from this stub file. As a result, Any is shown in various function signatures. The stub file should show None or the correct type, instead of the general Any.

Current stub generation process uses pyo3-stub-gen to auto generate the stub file. This will likely involve some sort of override.

[smartgoo]

This is largely addressed in PRs #26 and #28.

For functions that register callbacks, args and kwargs are intentionally left as typing.Any.

Needs another pass through.