docs: document dumi dev server port

Author: afc163

README.md

@@ -6,14 +6,12 @@
 
 <p align="center">English | <a href="./README.zh-CN.md">简体中文</a></p>
 
-
 <div align="center">
 
 [![NPM version][npm-image]][npm-url] [![npm download][download-image]][download-url] [![build status][github-actions-image]][github-actions-url] [![Codecov][codecov-image]][codecov-url] [![bundle size][bundlephobia-image]][bundlephobia-url] [![dumi][dumi-image]][dumi-url]
 
 </div>
 
-
 ## Highlights
 
 - Horizontal, vertical, and inline menu modes.
@@ -168,6 +166,8 @@ npm run compile
 npm run build
 ```
 
+The dumi site runs at `http://localhost:8000` by default.
+
 ## Release
 
 ```bash

README.zh-CN.md

@@ -166,6 +166,8 @@ npm run compile
 npm run build
 ```
 
+dumi 站点默认运行在 `http://localhost:8000`。
+
 ## 发布
 
 ```bash