Spawns seams on reset, explorables at random times after resets

[TwoOClock]

I really like the new explorables system. However, it currently forces people to go on a massive pillage spree right after a reset, since they don't seem to rotate or respawn. This makes them somewhat less palatable for people who aren't online in the first half hour or so after a reset, since the scavenge spots are always already scavenged. It might be funnier (and require more memory and dedicated treasure hunting during less active hours) to see them shift and appear/disappear after a while.

[Halfbrood]

Explorables and seams do spawn at random times during a reset (although a number do spawn specifically on module load).

It might be interesting to have them despawn, although we would need to investigate a way to ensure they don't spawn again (as they would be empty...)