🤔 [QUESTION]

### 🐛 where is "TooltipItem"
I want to know how to introduce this type "TooltipItem"
我想知道"TooltipItem"应该从那里引入

### 🏞 Expected result

### 🚑 Any additional [like screenshots]

i find this in website. i am using ts, so i want to know where is this "TooltipItem"
我在官网找到了这个，我正在使用ts，我想知道该如何引入这个类型

* **G2Plot Version**:^2.4.22
* **Platform**:

Start by locating the TypeScript definition and public exports for "TooltipItem" in the G2Plot v2.4.22 source, then compare them with the website example referenced in the issue. Done means the type's import path and usage are clearly documented for TypeScript users.

Written by the indexing model from the issue text.