fix: 调整Cogwheel子弹减速逻辑并移除Rooster测试代码

调整Cogwheel子弹的减速系数slow从乘以2改为固定0.5，使减速更平滑
移除Rooster角色中非发布版本的额外子弹数量测试代码

scripts/Contents/Characters/Rooster.gd

@@ -15,8 +15,6 @@ func register():
 				EffectController.create(ComponentManager.getEffect("BloodFall"), texture.global_position).shot()
 	)
 	chargeParticle.emitting = false
-	if !WorldManager.isRelease():
-		fields[FieldStore.Entity.EXTRA_BULLET_COUNT] = 3
 
 func ai():
 	texture.play("walk")