Add NodePath::slice method

[nlupugla]

Added slice(begin : int, end : int = INT_MAX) to NodePath.

Example usage:

^"Parent/Child:property".slice(0, -1) # returns ^"Parent/Child"

Closes godotengine/godot-proposals#7148.

Supersedes #78638.

[nlupugla]

PS: I'd love if someone could double check my index gymnastics. I tried to be pretty comprehensive with my test cases and was able to catch a few errors that way, but it never hurts to have another pair of eyes. In particular, if anyone can think of a way to make the logic a bit simpler, I'd be very grateful :)

[AThousandShips]

Maybe add a get_total_name_count to ease the integration

[nlupugla]

Maybe add a get_total_name_count to ease the integration

Were you thinking of adding this as an exposed method or just for internal use?

[AThousandShips]

Initially as just a c++ one, unless also adding a way to access any of the names, surnames or otherwise, with one operation, for convenience

[nlupugla]

Initially as just a c++ one, unless also adding a way to access any of the names, surnames or otherwise, with one operation, for convenience

That's not a bad idea and might simplify some of the existing code. That said, I think I'll leave that to a different PR.

I've added a get_total_name_count method as suggested.

[aaronfranke]

This looks good to me, it covers my use cases well with slice(0, x), and I think it's a good addition to NodePath.

[akien-mga]

Thanks!