TYP: write stubs where missing from imported libraries

[lucascolley]

This should allow us to make some of the type checking more strict:

array-api-extra/pyproject.toml

Lines 211 to 214 in 70d3e32

	# no array-api-strict type stubs
	reportUnknownMemberType = false
	# no array-api-compat type stubs
	reportUnknownVariableType = false