Update Natural Numbers Game build

Stream: general

[Andrii Kurdiumov]

@Jon Eugster it take a bit of time for me to reach Zulip, so as I said in https://github.com/leanprover-community/lean4game/issues/263 I'm willing to put time into updating things Natural Numbers game in way that's fine for you.

If you give me insights, what I can do, and what it's already there I would appreciate it. For example I do not fully understand what lean4web and what is lean4game for example.

[Jon Eugster]

Welcome to Zulip:blush: I'll DM you