feat: 添加Hitbox和Hurtbox，添加敌人和玩家之间的碰撞

scenes/components/hurtbox_component.gd

@@ -0,0 +1,19 @@
+extends Area2D
+class_name HurtboxComponent
+
+signal on_damaged(hitbox: HitboxComponent)
+
+
+# Called when the node enters the scene tree for the first time.
+func _ready() -> void:
+	pass # Replace with function body.
+
+
+# Called every frame. 'delta' is the elapsed time since the previous frame.
+func _process(delta: float) -> void:
+	pass
+
+
+func _on_area_entered(area: Area2D) -> void:
+	if area is HitboxComponent:
+		on_damaged.emit(area)