feat(Statemachine): 添加获取周期计时器方法并增强子弹过滤逻辑

为EntityBase添加getCycleTimer方法以直接获取计时器
修改CycleTimer的forceFilter方法以检查子弹是否正在销毁
更新InfinitySword的hitBullet逻辑以处理内部伤害子弹

scripts/Statemachine/CycleTimer.gd

@@ -15,7 +15,13 @@ func lifetime():
 func getStateAngle(index: int):
 	return lifetime() / period * deg_to_rad(360) - deg_to_rad(360.0 * index / len(bullets))
 func forceFilter():
-	bullets = bullets.filter(is_instance_valid)
+	bullets = bullets.filter(
+		func(b):
+			if b is BulletBase:
+				return !b.destroying
+			else:
+				return false
+	)
 func apply(where: Vector2):
 	forceFilter()
 	for index in len(bullets):

scripts/Statemachine/EntityBase.gd

@@ -227,6 +227,8 @@ func getOrCreateCycleTimer(timerName: String, period: float = 1000, distance: fl
 		if start: newTimer.start()
 		cycleTimers[timerName] = newTimer
 	return cycleTimers[timerName]
+func getCycleTimer(timerName: String):
+	return cycleTimers.get(timerName)
 func initHealth(maxHealth: float):
 	fields[FieldStore.Entity.MAX_HEALTH] = maxHealth
 	health = maxHealth