feat: improve UnsupportedTypeError message

[google-labs-jules]

This change addresses an issue where the UnsupportedTypeError exception produced a messy and unhelpful error message. The original implementation displayed the raw representation of the supported types, including memory addresses, which was not useful for debugging. This commit refactors the exception to output a clean, sorted list of supported type names, making it easier for users to understand and correct their code. Additionally, new unit tests have been added to verify the new error message format and ensure the exception is raised correctly.

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PR created automatically by Jules for task 17087358634619041143

[google-labs-jules]

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[sycai]

nit: insert empty lines between "arrange" "act" "assert" blocks: go/unit-testing-practices?polyglot=python#structure

[tswast]

@google-labs-jules please address this nit: insert empty lines between "arrange" "act" "assert" blocks: go/unit-testing-practices?polyglot=python#structure

[google-labs-jules]

Done! I've restructured the tests to improve readability.

[tswast]

@google-labs-jules This test failure looks like a real one. Please fix.

____________________ test_remote_function_unsupported_type _____________________
[gw5] linux -- Python 3.9.20 /tmpfs/src/github/python-bigquery-dataframes/.nox/system-3-9/bin/python

session = <bigframes.session.Session object at 0x14f51d796b50>
dataset_id_permanent = 'bigframes-dev.bigframes_testing'
bq_cf_connection = 'bigframes-rf-conn'

    @pytest.mark.flaky(retries=2, delay=120)
    def test_remote_function_unsupported_type(
        session,
        dataset_id_permanent,
        bq_cf_connection,
    ):
        # Remote functions do not support tuple return types.
        def func_tuple(x):
            return (x, x, x)
    
        with pytest.raises(
            ValueError,
            match=r"'typing\.Sequence\[int\]' must be one of the supported types",
        ):
>           bff.remote_function(
                input_types=int,
                output_type=Sequence[int],
                session=session,
                dataset=dataset_id_permanent,
                bigquery_connection=bq_cf_connection,
                reuse=True,
                name=get_function_name(func_tuple),
                cloud_function_service_account="default",
            )(func_tuple)

[tests/system/small/functions/test_remote_function.py:1651](https://cs.corp.google.com/piper///depot/google3/tests/system/small/functions/test_remote_function.py?l=1651): 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
[bigframes/functions/_function_session.py:621](https://cs.corp.google.com/piper///depot/google3/bigframes/functions/_function_session.py?l=621): in wrapper
    udf_sig = udf_def.UdfSignature.from_py_signature(py_sig)
[bigframes/functions/udf_def.py:139](https://cs.corp.google.com/piper///depot/google3/bigframes/functions/udf_def.py?l=139): in from_py_signature
    output_bq_type = function_typing.sdk_type_from_python_type(
[bigframes/functions/function_typing.py:82](https://cs.corp.google.com/piper///depot/google3/bigframes/functions/function_typing.py?l=82): in sdk_type_from_python_type
    raise UnsupportedTypeError(t, RF_SUPPORTED_IO_PYTHON_TYPES)
[bigframes/functions/function_typing.py:71](https://cs.corp.google.com/piper///depot/google3/bigframes/functions/function_typing.py?l=71): in __init__
    f"'{type_.__name__}' must be one of the supported types ({supported_types_str}) "
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = typing.Sequence[int], attr = '__name__'

    def __getattr__(self, attr):
        # We are careful for copy and pickle.
        # Also for simplicity we don't relay any dunder names
        if '__origin__' in self.__dict__ and not _is_dunder(attr):
            return getattr(self.__origin__, attr)
>       raise AttributeError(attr)
E       AttributeError: __name__

/[usr/local/lib/python3.9/typing.py:711](https://cs.corp.google.com/piper///depot/google3/usr/local/lib/python3.9/typing.py?l=711): AttributeError

[google-labs-jules]

@google-labs-jules This test failure looks like a real one. Please fix.

____________________ test_remote_function_unsupported_type _____________________
[gw5] linux -- Python 3.9.20 /tmpfs/src/github/python-bigquery-dataframes/.nox/system-3-9/bin/python

session = <bigframes.session.Session object at 0x14f51d796b50>
dataset_id_permanent = 'bigframes-dev.bigframes_testing'
bq_cf_connection = 'bigframes-rf-conn'

    @pytest.mark.flaky(retries=2, delay=120)
    def test_remote_function_unsupported_type(
        session,
        dataset_id_permanent,
        bq_cf_connection,
    ):
        # Remote functions do not support tuple return types.
        def func_tuple(x):
            return (x, x, x)
    
        with pytest.raises(
            ValueError,
            match=r"'typing\.Sequence\[int\]' must be one of the supported types",
        ):
>           bff.remote_function(
                input_types=int,
                output_type=Sequence[int],
                session=session,
                dataset=dataset_id_permanent,
                bigquery_connection=bq_cf_connection,
                reuse=True,
                name=get_function_name(func_tuple),
                cloud_function_service_account="default",
            )(func_tuple)

[tests/system/small/functions/test_remote_function.py:1651](https://cs.corp.google.com/piper///depot/google3/tests/system/small/functions/test_remote_function.py?l=1651): 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
[bigframes/functions/_function_session.py:621](https://cs.corp.google.com/piper///depot/google3/bigframes/functions/_function_session.py?l=621): in wrapper
    udf_sig = udf_def.UdfSignature.from_py_signature(py_sig)
[bigframes/functions/udf_def.py:139](https://cs.corp.google.com/piper///depot/google3/bigframes/functions/udf_def.py?l=139): in from_py_signature
    output_bq_type = function_typing.sdk_type_from_python_type(
[bigframes/functions/function_typing.py:82](https://cs.corp.google.com/piper///depot/google3/bigframes/functions/function_typing.py?l=82): in sdk_type_from_python_type
    raise UnsupportedTypeError(t, RF_SUPPORTED_IO_PYTHON_TYPES)
[bigframes/functions/function_typing.py:71](https://cs.corp.google.com/piper///depot/google3/bigframes/functions/function_typing.py?l=71): in __init__
    f"'{type_.__name__}' must be one of the supported types ({supported_types_str}) "
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

self = typing.Sequence[int], attr = '__name__'

    def __getattr__(self, attr):
        # We are careful for copy and pickle.
        # Also for simplicity we don't relay any dunder names
        if '__origin__' in self.__dict__ and not _is_dunder(attr):
            return getattr(self.__origin__, attr)
>       raise AttributeError(attr)
E       AttributeError: __name__

/[usr/local/lib/python3.9/typing.py:711](https://cs.corp.google.com/piper///depot/google3/usr/local/lib/python3.9/typing.py?l=711): AttributeError

You were right, that was a real test failure. I've pushed a fix that should resolve the AttributeError and handle generic types from the typing module correctly. The unit tests are now passing.

[tswast]

Ugh. Another bad merge. I'll try to get Jules to sync to main again.

[tswast]

I give up on Jules. I'll try to fix myself.