新增：Markdown编辑器/数据库优化/安全修复

- Markdown 编辑器：实时预览、PDF 导出、独立查看器
- 数据库优化：动态连接池、查询缓存、Redis Pipeline
- 窗口置顶功能
- 文件系统增强：右键菜单、编辑器集成、收藏夹重构
- 安全修复：XSS 防护、路径穿越、HTML 注入
- 代码质量：正则预编译、缓存锁优化、死代码清理

web/src/components/FileSystem/composables/useFilePreview.ts

@@ -3,10 +3,15 @@
  * 提供文件预览 URL 生成、媒体元数据获取等功能
  */
 
-import { ref, computed } from 'vue'
+import { ref } from 'vue'
 import { FILE_EXTENSIONS, FILE_SIZE_THRESHOLDS } from '@/utils/constants'
-import { normalizeFilePath } from '@/utils/fileUtils'
+import { normalizeFilePath, getExt } from '@/utils/fileUtils'
 import { detectFileTypeByContent } from '@/api/system'
+import {
+  isImageFile, isVideoFile, isAudioFile, isPdfFile,
+  isHtmlFile, isMarkdownFile, isPreviewable as isPreviewableType,
+  isTextEditable, isConfigFile
+} from '@/utils/fileTypeHelpers'
 import type { FilePreviewMetadata, FileType } from '@/types/file-system'
 
 // 内容检测大小限制（与后端一致）
@@ -81,159 +86,42 @@ export function useFilePreview(options: UseFilePreviewOptions = {}) {
   const getFileType = (filename: string): FileType => {
     if (!filename || typeof filename !== 'string') return 'Binary' as FileType
 
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
+    if (isImageFile(filename)) return 'Image' as FileType
+    if (isVideoFile(filename)) return 'Video' as FileType
+    if (isAudioFile(filename)) return 'Audio' as FileType
+    if (isPdfFile(filename)) return 'Pdf' as FileType
+    if (isHtmlFile(filename)) return 'Html' as FileType
+    if (isMarkdownFile(filename)) return 'Markdown' as FileType
+    if (FILE_EXTENSIONS.CODE.includes(getExt(filename))) return 'Code' as FileType
+    if (isConfigFile(filename)) return 'Code' as FileType
+    if (isTextEditable(filename)) return 'Text' as FileType
 
-    // 图片
-    if (FILE_EXTENSIONS.IMAGE.includes(ext)) {
-      return 'Image' as FileType
-    }
-
-    // 视频
-    if (FILE_EXTENSIONS.VIDEO.includes(ext)) {
-      return 'Video' as FileType
-    }
-
-    // 音频
-    if (FILE_EXTENSIONS.AUDIO.includes(ext)) {
-      return 'Audio' as FileType
-    }
-
-    // PDF
-    if (ext === 'pdf') {
-      return 'Pdf' as FileType
-    }
-
-    // HTML
-    if (['html', 'htm'].includes(ext)) {
-      return 'Html' as FileType
-    }
-
-    // Markdown
-    if (['md', 'markdown'].includes(ext)) {
-      return 'Markdown' as FileType
-    }
-
-    // 代码
-    if (FILE_EXTENSIONS.CODE.includes(ext)) {
-      return 'Code' as FileType
-    }
-
-    // 配置文件（返回 Code 类型，因为它们也是可编辑的文本格式）
-    if (FILE_EXTENSIONS.CONFIG.includes(ext)) {
-      return 'Code' as FileType
-    }
-
-    // 文本
-    if (FILE_EXTENSIONS.TEXT.includes(ext)) {
-      return 'Text' as FileType
-    }
-
-    // 默认为二进制
     return 'Binary' as FileType
   }
 
-  /**
-   * 判断是否为图片文件
-   */
-  const isImageFile = (filename: string): boolean => {
-    if (!filename || typeof filename !== 'string') return false
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
-    return FILE_EXTENSIONS.IMAGE.includes(ext)
-  }
-
-  /**
-   * 判断是否为视频文件
-   */
-  const isVideoFile = (filename: string): boolean => {
-    if (!filename || typeof filename !== 'string') return false
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
-    return FILE_EXTENSIONS.VIDEO.includes(ext)
-  }
-
-  /**
-   * 判断是否为音频文件
-   */
-  const isAudioFile = (filename: string): boolean => {
-    if (!filename || typeof filename !== 'string') return false
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
-    return FILE_EXTENSIONS.AUDIO.includes(ext)
-  }
-
-  /**
-   * 判断是否为 PDF 文件
-   */
-  const isPdfFile = (filename: string): boolean => {
-    if (!filename || typeof filename !== 'string') return false
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
-    return ext === 'pdf'
-  }
-
-  /**
-   * 判断是否为 HTML 文件
-   */
-  const isHtmlFile = (filename: string): boolean => {
-    if (!filename || typeof filename !== 'string') return false
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
-    return ['html', 'htm'].includes(ext)
-  }
-
-  /**
-   * 判断是否为 Markdown 文件
-   */
-  const isMarkdownFile = (filename: string): boolean => {
-    if (!filename || typeof filename !== 'string') return false
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
-    return ['md', 'markdown'].includes(ext)
-  }
-
-  /**
-   * 判断是否为代码文件
-   */
-  const isCodeFile = (filename: string): boolean => {
-    if (!filename || typeof filename !== 'string') return false
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
-    return FILE_EXTENSIONS.CODE.includes(ext)
-  }
-
-  /**
-   * 判断是否为文本文件
-   */
-  const isTextFile = (filename: string): boolean => {
-    if (!filename || typeof filename !== 'string') return false
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
-    return FILE_EXTENSIONS.TEXT.includes(ext)
-  }
-
   /**
    * 判断文件是否可预览
    */
   const isPreviewable = (filename: string): boolean => {
     if (!filename || typeof filename !== 'string') return false
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
-    return FILE_EXTENSIONS.IMAGE.includes(ext) ||
-           FILE_EXTENSIONS.VIDEO.includes(ext) ||
-           FILE_EXTENSIONS.AUDIO.includes(ext) ||
-           ext === 'pdf' ||
-           ['html', 'htm'].includes(ext) ||
-           ['md', 'markdown'].includes(ext)
+    return isPreviewableType(filename)
   }
 
   /**
    * 判断文件是否可编辑
    */
   const isEditable = (filename: string, fileSize: number): boolean => {
-    // 检查文件大小
     if (fileSize > FILE_SIZE_THRESHOLDS.BIG_FILE) {
       return false
     }
 
-    // 检查文件类型
     if (!filename || typeof filename !== 'string') return false
-    const ext = filename.split('.').pop()?.toLowerCase() || ''
+    const ext = getExt(filename)
     return FILE_EXTENSIONS.CODE.includes(ext) ||
-           FILE_EXTENSIONS.TEXT.includes(ext) ||
-           FILE_EXTENSIONS.CONFIG.includes(ext) ||
-           ['html', 'htm', 'md', 'markdown'].includes(ext)
+           isTextEditable(filename) ||
+           isConfigFile(filename) ||
+           isHtmlFile(filename) ||
+           isMarkdownFile(filename)
   }
 
   /**
@@ -306,8 +194,6 @@ export function useFilePreview(options: UseFilePreviewOptions = {}) {
     isPdfFile,
     isHtmlFile,
     isMarkdownFile,
-    isCodeFile,
-    isTextFile,
     isPreviewable,
     isEditable,