tests

WIP: prototype MDX protocol #4649

Job	Run time
integration tests (windows-latest, 3.9)	1m 46s
unit tests (3.9)	6h 0m 12s
unit tests (3.13)	1m 3s
integration tests (windows-latest, 3.13)	1m 44s
integration tests (macos-latest, 3.13)	1m 12s
integration tests (ubuntu-latest, 3.9)	49s
integration tests (ubuntu-latest, 3.13)	59s
integration tests (macos-latest, 3.9)	1m 43s
	6h 9m 28s

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