Refactor counter setup and update various classes

The `overcooked_environment.py` file has been significantly refactored to streamline handling of counter setup. Post counter setup responsibilities have been shifted to the `CounterFactory` class. A utility function, `get_closest`, has been introduced in `utils.py` to determine the closest counter and is used in multiple classes. Minor updates are also made across several other classes for optimization and clarity. The 'other' score in `environment_config.yaml` has been changed from 0 to 20.