CQL2 CASEI support for sqlalchemy backend?

[mikemahoney218-usgs]

CQL2's CASEI function is supported in parsing, but is not supported by the sqlalchemy backend:

Python 3.12.8 (main, Jan  5 2025, 06:55:30) [Clang 19.1.6 ] on darwin
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>>> from sqlalchemy import Column, String
>>> from pygeofilter.parsers.cql2_text import parse
>>> from pygeofilter.backends.sqlalchemy.evaluate import to_filter
>>> to_filter(parse("road_class IN ('Οδος','Straße')"), { "road_class": Column(String) })
<sqlalchemy.sql.elements.BinaryExpression object at 0x12241bf80>
>>> to_filter(parse("CASEI(road_class) IN (CASEI('Οδος'),CASEI('Straße'))"), { "road_class": Column(String) })
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/mjmahoney/codebase/scratch/pygeofilter_test/.venv/lib/python3.12/site-packages/pygeofilter/backends/sqlalchemy/evaluate.py", line 148, in to_filter
    return SQLAlchemyFilterEvaluator(field_mapping, undefined_as_null).evaluate(ast)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/mjmahoney/codebase/scratch/pygeofilter_test/.venv/lib/python3.12/site-packages/pygeofilter/backends/evaluator.py", line 103, in evaluate
    sub_args = [self.evaluate(sub_node, False) for sub_node in subnodes]
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/mjmahoney/codebase/scratch/pygeofilter_test/.venv/lib/python3.12/site-packages/pygeofilter/backends/evaluator.py", line 111, in evaluate
    result = self.adopt(node, *sub_args)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/Users/mjmahoney/codebase/scratch/pygeofilter_test/.venv/lib/python3.12/site-packages/pygeofilter/backends/evaluator.py", line 122, in adopt
    raise NotImplementedError(f"Failed to evaluate node of type {type(node)}")
NotImplementedError: Failed to evaluate node of type <class 'pygeofilter.ast.Function'>
# note that parse works fine, the error arises in the evaluation
>>> parse("CASEI(road_class) IN (CASEI('Οδος'),CASEI('Straße'))"), { "road_class": Column(String) }
(In(lhs=Function(name='lower', arguments=[ATTRIBUTE road_class]), sub_nodes=[Function(name='lower', arguments=['Οδος']), Function(name='lower', arguments=['Straße'])], not_=False), {'road_class': Column(None, String(), table=None)})

Is there any chance this could be supported by the sqlalchemy backend?