[Experimental] 启用 item 分页功能 | Enable item paging

[weinibuliu]

item 分页功能于 v1.11.0 版本加入，目的是解决 item 过多/生成过快导致的性能问题。这个功能目前仍然是实验性的，因此它默认被禁用。如果希望体验这一功能，请修改环境变量 MAADBG_PER_PAGE_ITEM_NUM 为任意正整数 (推荐为 200-400) 。如果遇到任何问题，欢迎提交 issue 向我们反馈。

Item paging was added in v1.11.0 to address performance issues caused by too many items or too fast item generation. Currently, this feature is still experimental and is disabled by default. If you would like to try it, please modify the environment variable MAADBG_PER_PAGE_ITEM_NUM to any positive integer (recommended 200 to 400). If you encounter any problems, please submit an issue to give us feedback.

[miaojiuqing]

非常好item 分页功能，使我测试自动战斗不再电脑卡顿