feat(武器): 为弓武器添加生命汲取和升华选项

添加生命汲取效果，使箭矢命中时回复生命值
实现弓武器的升华系统，包含5种不同品质的强化选项
调整攻击逻辑以支持升华效果和生命值相关的伤害加成

scripts/Contents/Bullets/Arrow.gd

@@ -6,6 +6,7 @@ class_name Arrow
 var atk: float = 0
 var waitTime: float = 0
 var offsetRotation: float = 0
+var lifesteal: float = 0.2
 
 func register():
 	trail.emitting = false
@@ -23,6 +24,7 @@ func ai():
 	PresetBulletAI.forward(self , rotation)
 	if speed < 1:
 		tryDestroy()
-func succeedToHit(_dmg: float, _entity: EntityBase):
+func succeedToHit(_dmg: float, entity: EntityBase):
 	var effect = EffectController.create(ComponentManager.getEffect("ShootBlood"), position)
 	effect.shot()
+	entity.heal(lifesteal)