Cleanup timers sometimes fail to trigger expiration callback

[zrisher]

As discussed, sometimes timers will fail to trigger the expiration method. Demonstrated in https://github.com/zrisher/GardenConquest/tree/derelict-timer-bugshow with a copy of the current world.

[zrisher]

I'm starting to think this happens because state is saved every 5 minutes and cleanup increments are usually set to increments of 5 min. State save happens first, just before, so the timers are loaded as expired but their internal timers are discarded, so the callback never actually gets triggered.