feat(资源处理): 添加无扩展名和根路径资源的处理逻辑

- 无扩展名资源根据类型自动补全.css或.js扩展名
- 根路径资源使用主机名作为首层目录避免跨域冲突
- 更新README文档说明新增规则

README.md

@@ -133,6 +133,13 @@
 - 类型判定：优先扩展名（`.css`/`.js`），其次 `Content-Type`
 - 安全加固：移除 `..` 等越权片段，写入前校验不越界（`server.js:65` 起）
 
+### 规则补充（无扩展名与根路径资源）
+
+- 无扩展名的资源将根据类型自动补全扩展名：`text/css` → `.css`、`application/text-javascript`/`text/javascript` → `.js`
+- 根路径资源（如 `https://cdn.tailwindcss.com`）为避免跨域冲突，将以主机名作为首层目录：
+  - 本地保存：`cache/js/cdn.tailwindcss.com/index.js`
+  - 对外访问：`/js/cdn.tailwindcss.com/index.js`
+
 ## 去重策略
 
 - 目标路径存在则跳过抓取，响应中返回 `skipped: true`

seed.txt

@@ -3,4 +3,5 @@
 
 # Bootstrap 5.3.0 样式与脚本
 https://cdn.jsdmirror.com/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css
-https://cdn.jsdmirror.com/npm/bootstrap@5.3.0/dist/js/bootstrap.bundle.min.js
+https://cdn.jsdmirror.com/npm/bootstrap@5.3.0/dist/js/bootstrap.bundle.min.js
+https://cdn.tailwindcss.com

server.js

@@ -65,7 +65,7 @@ function resolveTargetPath(urlStr, contentType) {
   const u = new URL(urlStr)
   let base = path.basename(u.pathname)
   if (!base || base === '/') base = 'index'
-  const ext = path.extname(base).toLowerCase()
+  let ext = path.extname(base).toLowerCase()
 
   let folder
   let type
@@ -84,6 +84,12 @@ function resolveTargetPath(urlStr, contentType) {
   else if ((contentType || '').split(';')[0].trim() === 'text/css') type = 'css'
   else type = 'js'
 
+  // 无扩展名时根据判定类型补全扩展名，确保同一URL在抓取前后路径一致
+  if (!ext) {
+    if (type === 'css') { base = `${base}.css`; ext = '.css' }
+    else { base = `${base}.js`; ext = '.js' }
+  }
+
   // 按原URL路径的目录层级保存：/npm/bootstrap@5.3.0/dist/css → 子目录
   let subDir = path.dirname(u.pathname)
   if (subDir === '/' || subDir === '.') subDir = ''
@@ -92,7 +98,8 @@ function resolveTargetPath(urlStr, contentType) {
   const safeParts = raw
     .split('/')
     .filter(p => p && p !== '..')
-  const normalized = safeParts.join('/')
+  let normalized = safeParts.join('/')
+  if (!normalized) normalized = u.hostname
   const targetDir = normalized ? path.join(folder, normalized) : folder
 
   let fullPath = path.join(targetDir, base)
@@ -116,7 +123,8 @@ function sanitizeSubdirFromUrl(urlStr) {
   if (subDir === '/' || subDir === '.') subDir = ''
   const raw = subDir.replace(/^\/+/, '').replace(/\\+/g, '/')
   const safeParts = raw.split('/').filter(p => p && p !== '..')
-  return safeParts.join('/')
+  const joined = safeParts.join('/')
+  return joined ? joined : u.hostname
 }
 
 /**