Add Optional 'Criteria' Parameter (Strength or Serviceability) to the 'add' Method in LoadCombinations Class

[Jeroen124]

Problem

The add method of the LoadCombinations class currently lacks an optional parameter for specifying the criteria. This results in a discrepancy between the output generated by the Python package and the expected input format for the API solver.

class LoadCombinations(ModelCollectionComponent):
    """Creates an instance of the SkyCiv LoadCombinations class.
    """

    def add(self, name: str, combination_factors: dict) -> int:
        """Adds a new load combination.

        Args:
            name (str): The name of the load combination.
            combination_factors (dict): Key value pairs for the factors to apply to the load groups.

        Returns:
            int: The ID of the created load combination.

        Example::

            lcs = LoadCombinations()

            factors = {
                "SW": 1,
                "windCase": 1,
                "liveLoad": 1.5
            }

            lcs.add("LC1", factors)
        """
        next_index = next_object_key(self)

        lc = LoadCombination(name, combination_factors)
        setattr(self, str(next_index), lc)

        return next_index

This gives te following input for the solver, resulting from the python package.

                    "load_combinations": {
                        "1": {
                            "name": "ULS1",
                            "Dead_load": 1.35,
                            "Product_load_1": 1.5750000000000002
                        },

Whilst the api solver expects something like this:

        "1": {
            "name": "LC1",
            "criteria": "strength"
        },

Possible solution:

class LoadCombinations(ModelCollectionComponent):
    """Creates an instance of the SkyCiv LoadCombinations class.
    """

    def add(self, name: str, combination_factors: dict, criteria: str = None) -> int:
        """Adds a new load combination.

        Args:
            name (str): The name of the load combination.
            combination_factors (dict): Key value pairs for the factors to apply to the load groups.
            criteria (str, optional): The criteria for the load combination (e.g., 'strength', 'serviceability'). Defaults to None.

        Returns:
            int: The ID of the created load combination.

        Example::

            lcs = LoadCombinations()

            factors = {
                "SW": 1,
                "windCase": 1,
                "liveLoad": 1.5
            }

            lcs.add("LC1", factors, criteria="strength")
        """
        next_index = next_object_key(self)

        lc = LoadCombination(name, combination_factors, criteria)
        setattr(self, str(next_index), lc)

        return next_index