Function to_rust_partition_evaluator 

pub fn to_rust_partition_evaluator(
    evaluator: Py<PyAny>,
) -> PartitionEvaluatorFactory

Wrap a Python evaluator factory in a PartitionEvaluatorFactory.

Retained for downstream callers that previously consumed this helper to build a PartitionEvaluatorFactory for factory-based APIs. New in-crate code should construct a PythonFunctionWindowUDF directly so the codec can downcast and ship it inline.