Validate xarray-kat schema against xradio

[sjperkins]

• Closes Check the produced DataTree schema against the MSv4 spec #12

Thanks for contributing to xarray-kat.

We would appreciate it if you could add:

• Test Cases covering your PR.
• Documentation.
• A Changelog entry in doc/source/changelog.rst.

[sjperkins]

Test cases fail for 367d6cf as there isn't yet a 3.14 install for xradio.

This masks an xradio import failure that manifests on earlier python versions

$ uv run --extra testing py.test -s -vvv tests/ --pdb
========================================================================================== test session starts ===========================================================================================
platform linux -- Python 3.11.14, pytest-8.4.2, pluggy-1.6.0 -- /home/simon/code/xarray-kat/.venv/bin/python3
cachedir: .pytest_cache
rootdir: /home/simon/code/xarray-kat
configfile: pyproject.toml
plugins: pytest_httpserver-1.1.3
collecting ... 
>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> traceback >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
ImportError while importing test module '/home/simon/code/xarray-kat/tests/test_xradio.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
.venv/lib/python3.11/site-packages/_pytest/python.py:498: in importtestmodule
    mod = import_path(
.venv/lib/python3.11/site-packages/_pytest/pathlib.py:587: in import_path
    importlib.import_module(module_name)
/usr/lib/python3.11/importlib/__init__.py:126: in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
<frozen importlib._bootstrap>:1204: in _gcd_import
    ???
<frozen importlib._bootstrap>:1176: in _find_and_load
    ???
<frozen importlib._bootstrap>:1147: in _find_and_load_unlocked
    ???
<frozen importlib._bootstrap>:690: in _load_unlocked
    ???
.venv/lib/python3.11/site-packages/_pytest/assertion/rewrite.py:186: in exec_module
    exec(co, module.__dict__)
tests/test_xradio.py:3: in <module>
    import xradio.measurement_set  # noqa: F401 Required to register types for check_datatree
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.venv/lib/python3.11/site-packages/xradio/measurement_set/__init__.py:9: in <module>
    from .processing_set_xdt import ProcessingSetXdt
.venv/lib/python3.11/site-packages/xradio/measurement_set/processing_set_xdt.py:5: in <module>
    from xradio.measurement_set.measurement_set_xdt import get_data_group_name
.venv/lib/python3.11/site-packages/xradio/measurement_set/measurement_set_xdt.py:9: in <module>
    from xradio._utils.xarray_helpers import get_data_group_name, create_new_data_group
.venv/lib/python3.11/site-packages/xradio/_utils/xarray_helpers.py:2: in <module>
    from xradio._utils.schema import get_data_group_keys
.venv/lib/python3.11/site-packages/xradio/_utils/schema.py:1: in <module>
    import toolviper.utils.logger as logger
E   ModuleNotFoundError: No module named 'toolviper'