Pokemon Emerald: Change Lilycove access logic

[Zunawe]

What is this fixing or adding?

There's a sort of happy accident in the region connections between Lilycove City and Route 124. REGION_ROUTE124/MAIN should connect to REGION_LILYCOVE_CITY/SEA, but it's instead connected to REGION_LILYCOVE_CITY/MAIN. It should probably have also had a rule on it preventing traversal from east to west if there are wailmer there, just as you're prevented from going west to east if there are wailmer there.

It was unknown to me until recently, but that is, in fact, how the game behaves. The wall does not exist until you load the map on the west side. Then when you clear the story events that remove it, it goes away again. This would have potentially caused a softlock except that the only way to cross from east to west is to have flown (fast traveled) to a city on the east side via your free fly location. And once you've loaded the wall, you have the ability to fly to Lilycove again as well.

So nothing about the current behavior actually causes any problems, but it's so obscure and unintuitive that I'm going to fix it anyway. I thought about waiting until I could find a way to block you in the game as well, but it turns out to not be trivial, and out of logic access isn't a big deal.

So this changes logic to assume the Lilycove wailmer are a 2-way wall. And it adds some tests that I wrote while checking it.

How was this tested?

New test. Generated a game.

[ScipioWright]

It gens, tests pass, what more could you ask for?

[Exempt-Medic]

Tests pass, generation succeeds, and the region mapping updates accordingly