feat: Array windows and chunks API from Rust

[hargoniX]

Right now without the respective reverse chunks functions to check if this API design is fine before doing it wrong twice.

[joehendrix]

Are there other projects using this? I think we are potentially better served more abstract than this in Std, but I'm not quite sure how this is used.

[hargoniX]

This PR (like my other Array based one) was inspired by the Rust API functions for Vec (https://doc.rust-lang.org/stable/std/vec/struct.Vec.html) since Lean often tends to copy Rust functionality I thought it might be a good idea to put it into our stdlib as well.

[fgdorais]

Heartbeat check: is this PR still active? If it is then just give a thumbs up and I will delete this comment.

[hargoniX]

I'm not going to invest more time in it.

[fgdorais]

Understood. I'm removing awaiting-author and adding help-wanted to signal that this PR is "for adoption".