docs: install with pnpm (#9850)

packages/vant/docs/markdown/quickstart.en-US.md

@@ -5,11 +5,17 @@
 ### npm
 
 ```bash
-# Install Vant 2 for Vue 2 project
-npm i vant -S
+# install Vant 2 for Vue 2 project
+npm i vant@2
 
-# Install Vant 3 for Vue 3 project
-npm i vant@next -S
+# install Vant 3 for Vue 3 project
+npm i vant@3
+
+# with yarn
+yarn add vant@3
+
+# with pnpm
+pnpm add vant@3
 ```
 
 ### CDN

packages/vant/docs/markdown/quickstart.zh-CN.md

@@ -8,14 +8,20 @@
 
 ### 通过 npm 安装
 
-在现有项目中使用 Vant 时，可以通过 `npm` 或 `yarn` 进行安装：
+在现有项目中使用 Vant 时，可以通过 `npm`、`yarn` 或 `pnpm` 进行安装：
 
 ```bash
-# Vue 2 项目，安装 Vant 2：
-npm i vant -S
+# Vue 2 项目，安装 Vant 2
+npm i vant@2
 
-# Vue 3 项目，安装 Vant 3：
-npm i vant@next -S
+# Vue 3 项目，安装 Vant 3
+npm i vant@3
+
+# 通过 yarn 安装
+yarn add vant@3
+
+# 通过 pnpm 安装
+pnpm add vant@3
 ```
 
 ### 通过 CDN 安装

packages/vant/src/area/README.md

@@ -55,7 +55,14 @@ export default {
 Vant officially provides a default area data, which can be imported through [@vant/area-data](https://github.com/youzan/vant/tree/dev/packages/vant-area-data):
 
 ```bash
+# with npm
+npm i @vant/area-data
+
+# with yarn
 yarn add @vant/area-data
+
+# with pnpm
+pnpm add @vant/area-data
 ```
 
 ```ts

packages/vant/src/area/README.zh-CN.md

@@ -57,7 +57,14 @@ const areaList = {
 Vant 官方提供了一份默认的省市区数据，可以通过 [@vant/area-data](https://github.com/youzan/vant/tree/dev/packages/vant-area-data) 引入：
 
 ```bash
+# 通过 npm
+npm i @vant/area-data
+
+# 通过 yarn
 yarn add @vant/area-data
+
+# 通过 pnpm
+pnpm add @vant/area-data
 ```
 
 ```ts