mfi-M3GNet implementation is added

[kenko911]

Summary

The mfi-M3GNet model is now available by enabling the hyparameters for n_state_types and state_embedding_dim. Moreover, a variable "state_attr" is also available for performing calculations with multi-fidelity M3GNet.

Checklist

• Google format doc strings added. Check with ruff.
• Type annotations included. Check with mypy.
• Tests added for new features/fixes.
• If applicable, new classes/functions/modules have duecredit @due.dcite decorators to reference relevant papers by DOI (example)

Tip: Install pre-commit hooks to auto-check types and linting before every commit:

pip install -U pre-commit
pre-commit install