docs: add instructions for bun package manager (#12182)

packages/vant-cli/README.md

@@ -32,6 +32,9 @@ yarn add @vant/cli -D
 
 # via pnpm
 pnpm add @vant/cli -D
+
+# via Bun
+bun add @vant/cli -D
 ```
 
 Please add the followed config to `package.json` file.

packages/vant-cli/README.zh-CN.md

@@ -29,6 +29,9 @@ yarn add @vant/cli -D
 
 # 通过 pnpm
 pnpm add @vant/cli -D
+
+# 通过 Bun
+bun add @vant/cli -D
 ```
 
 安装完成后，请将以下配置添加到 package.json 文件中

packages/vant-cli/docs/config.md

@@ -218,7 +218,7 @@ If you need to configure some vite plugins, please create a `vite.config.ts` fil
 
 ### build.packageManager
 
-- Type: `'npm' | 'yarn' | 'pnpm'`
+- Type: `'npm' | 'yarn' | 'pnpm' | 'bun'`
 - Default: `yarn`
 
 `npm` package manager.

packages/vant-cli/docs/config.zh-CN.md

@@ -220,7 +220,7 @@ module.exports = {
 
 ### build.packageManager
 
-- Type: `'npm' | 'yarn' | 'pnpm'`
+- Type: `'npm' | 'yarn' | 'pnpm' | 'bun'`
 - Default: `yarn`
 
 指定使用的包管理器。