Counter gate move cost

[Procyonae]

Summary

Bugfixes "Open counter gates are faster to navigate than counters"

Purpose of change

Partially addresses #66423

Describe the solution

Open counter gate now has no move cost penalty over the base terrain

Describe alternatives you've considered

Making the closed gate -10 mod instead but them it says "Impassable" which doesn't make much sense so I just moved it in line with the open gate

Making it 1 move cost mod instead but as it is now with opening taking 100 it still takes about the same to open and move through the gate as going over the counter so 0 move cost mod seems to make more sense

Giving counter gates the ability to be examine climbed for the same movecost as navigating the regular counter but the only climb action costs 400 and I don't fancy making a c++ change for something so minor

I looked at counters and cupboards because they have kind of odd similarities/differences but I couldn't decide what to do with them so I left them as is

Testing

Additional context

[Demivan]

It is a good addition, but it does not fully solve #66423. I think it is better to keep the issue open.