Improve ship crafter and hangar controls

Fleet.gd

@@ -92,6 +92,23 @@ func add_ship(vessel_type: String = GameState.VESSEL_INTERCEPTOR) -> bool:
 	return true
 
 
+func store_ship(index: int) -> String:
+	# A fleet always keeps one ship deployed. Removing the last one would trip
+	# the wiped-out-fleet safety net on the next frame and immediately spawn a
+	# replacement, which is the opposite of storing it at the mothership.
+	if ships.size() <= 1 or index < 0 or index >= ships.size():
+		return ""
+	var ship: Node = ships[index]
+	if not is_instance_valid(ship):
+		return ""
+	var vessel_type: String = String(ship.vessel_type)
+	ships.remove_at(index)
+	formation_offsets.remove_at(index)
+	ship.queue_free()
+	apply_formation()
+	return vessel_type
+
+
 func apply_formation() -> void:
 	# Re-seats the EXISTING ships into the current GameState.formation.
 	# Without this, editing the layout at a command centre (or pivoting it)