GunkNode has distinct destroy & collect methods

src/world/gunk_node/gunk_node.gd

@@ -41,6 +41,12 @@ func _process(_delta: float) -> void:
 	_hit_this_frame = false
 
 	if _sustained_damage >= durability:
+		collect()
+
+
+## Destroy this node, with the player collecting the grunk value.
+func collect() -> void:
+	Game.manager.collect_grunk(value)
 	destroy()