Saves load right away now

The simulation is deterministic, the same world seed and the same inputs always give exactly the same game. So the first save system was the lazy one, a save file was the seed plus a list of every command you gave, and loading it replayed the entire game from the first tick behind a progress bar.

That's fine for a 5 minute colony and bad for one that's been going for two years.

Saves are snapshots now. The file holds the whole state of the world (every cell, every ant, the scent trails, the temperature) and loading it is close to instant. The part I cared about most is that a loaded game carries on exactly as if you never stopped, and there's a test that loads a save and checks that every tick after it matches the original run.

There's a quick save on F5, quick load on F9 and an autosave every 5 minutes. The old recorded saves still load the slow way.