If multiple harvesters are ordered to return to refinery not all of them will actually dump resources

[stefanhendriks]

To reproduce:

• have 2 or more harvesters, and 1 refinery
• let harvesters harvest, but not be entirely full!
• order all harvesters to return to refinery
• all harvesters will move to refinery
• 1 will enter refinery
• the other(s) will stop/seek spice again

this is because the harvesters, once they arrived at/near the refinery have no memory of that they where supposed to dump spice.

[stefanhendriks]

This can be resolved by having actual Goals and Tasks (like the Fear AI idiom). Ie, the harvester would then remember it was supposed to dump resources.