Give updateUnitPositions for DF a return if a unit is able to cap, so we can notify players if they can't capture
Return should be an array [true, true, true, false] in the same order as the input. That way in SQF we can send a target event to units if their capturing status changed.
Right now often it feels like players don't realize they can't capture if they're behind lines / on an island This would allow us to relatively efficiently (performance / broadcasting wise) send them a heads up