Make Range(step) obsolete and add primitive overloads to Sequence/InfiniteSequence

[neuecc]

I didn't expect the step Range(Sequence/InfiniteSequence) to be added in standard quickly. I want to minimize custom extensions, so I'd like to deprecate features that overlap. Instead, for Sequence/InfiniteSequence, which currently requires .NET 8 or higher, I'll add primitive overloads (similar to Sum and Max) to make them available on all platforms.