Add stateless doc, prefer stateless mode and disable legacy SSE by default #2558

Job	Run time
build (windows-latest, Release)	11m 9s
build (ubuntu-latest, Debug)	13m 3s
build (ubuntu-latest, Release)	13m 20s
build (windows-latest, Debug)	11m 35s
build (macos-latest, Release)	5m 9s
build (macos-latest, Debug)	6m 11s
publish-coverage	0s
	1h 0m 27s

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