Add AFK logout timer to Limsa

[Packetdancer]

We should've just let Leviathan have it.

Hey, don't bring my server into this. What'd we ever do to you?

More seriously, the Firmament timer is—as I understand it—one that kicks you out of the Firmament, bumping you back out to the Ishgard aetheryte; the Firmament is, so far as I know, a special instance case—i.e., a zone handled differently than other areas of the game—not technically the open world, so it's more the equivalent of being bumped from a duty for being idle. Given the usual spaghetti code claims, they might not be able to add a logout timer to a specific zone in the main world versus the whole open world.