fix: range contains(), is_in_range() to use nvim equivalents

[kiyoon]

Changes most functions to accept generic Range type instead of only accepting a specific type thus converting the type when calling them.

Mainly changed shared.torange4() -> _range.unpack4() to achieve this.

[clason]

This is the correct approach, IMO. (My plan is to be aggressive when dropping support in nvim-treesitter#main, so hopefully this won't be long.)