docs: 品牌升级，优化 README 风格

scripts/generate-sitemap.mjs

@@ -33,6 +33,7 @@ const getBaseUrl = () => {
 }
 
 const siteUrl = getBaseUrl()
+const skipSitemapWrite = process.env.SITEMAP_NO_WRITE === '1'
 
 // 扫描目录中的所有 markdown 文件
 function scanMarkdownFiles(dir, basePath = '') {
@@ -235,6 +236,11 @@ function main() {
     }
   }
 
+  if (skipSitemapWrite) {
+    shouldWrite = false
+    console.log('⏭️  SITEMAP_NO_WRITE=1, skipping sitemap write')
+  }
+
   if (shouldWrite) {
     fs.writeFileSync(outputPath, sitemapXml, 'utf-8')
     console.log(`✅ Sitemap generated at ${outputPath}`)