fix(武器/子弹): 调整子弹速度和能量衰减

修改Pipe武器的子弹速度计算方式，使用平方根函数平滑速度增长
将Pipe子弹命中后的能量衰减系数从0.8改为0.6，加快能量消耗

scripts/Contents/Bullets/PipeBullet.gd

@@ -11,4 +11,4 @@ func ai():
 func destroy(_beacuseMap: bool):
 	EffectController.create(ComponentManager.getEffect("PipeFall"), position).shot()
 func succeedToHit(_dmg: float, _entity: EntityBase):
-	energy *= 0.8
+	energy *= 0.6

scripts/Contents/Weapons/Pipe.gd

@@ -16,5 +16,5 @@ func attack(entity: EntityBase):
 			var e = charged(readStore("atk"), 0.1)
 			bullet.baseDamage = e
 			bullet.energy = e
-			bullet.speed = e
+			bullet.speed = sqrt(e)
 	return true