Add scatter with reduction support #10728

Job	Run time
runner-preparation / prepare	4s
pre-commit / pre-commit (code formatting)	52s
integration-tests-nvidia / integration-tests-nvidia (nvidia-h100)	24m 58s
integration-tests-nvidia / integration-tests-nvidia (nvidia-gb200)	25m 13s
integration-tests-nvidia / integration-tests-nvidia (nvidia-a100)	18m 37s
integration-tests-amd / integration-tests-amd (amd-gfx950)	13m 7s
integration-tests-amd / integration-tests-amd (self-hosted, gfx90a)	12m 51s
build-macos / Build MacOS (macos-latest)	25m 5s
integration-tests-amd / integration-tests-amd (amd-gfx942)	14m 20s
	2h 15m 7s

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