新增: 资源管理器文件粘贴到文件列表

- 后端 ReadClipboardFiles 读系统剪贴板 CF_HDROP 拿路径列表
- Ctrl+V 优先粘贴系统剪贴板文件，复用拖入导入链路（SFTP 上传/本机复制/目录递归）
- 补齐设计文档记录的历史缺口（Wails 限制未做）

frontend/src/components/FileSystem/index.vue

@@ -129,6 +129,7 @@ import { ref, computed, onMounted, onUnmounted, watch, nextTick } from 'vue'
 import { getPathSeparator } from '@/utils/fileUtils'
 import { Message, Modal } from '@arco-design/web-vue'
 import { On, Off } from '@wailsio/events'
+import { ReadClipboardFiles } from '@bindings/u-desk/app'
 import { renderMarkdown, parseMarkdown, isMarkedReady, preloadMarked, renderMermaidDiagrams, rerenderMermaidDiagrams, setCurrentFileDir, setFileServerBase } from '@/utils/markedExtensions'
 import { useThemeStore } from '@/stores/theme'
 import { useTransferStore } from '@/stores/transfer'
@@ -2023,6 +2024,17 @@ const handlePaste = async (event: ClipboardEvent) => {
   const target = event.target as HTMLElement
   if (target.tagName === 'INPUT' || target.tagName === 'TEXTAREA' || target.isContentEditable) return
 
+  // 系统剪贴板文件（资源管理器复制，文件+文件夹）优先：
+  // 后端读 CF_HDROP 拿真实路径（DOM paste 拿不到文件夹），复用拖入导入链路
+  try {
+    const sysPaths = await ReadClipboardFiles()
+    if (sysPaths && sysPaths.length > 0) {
+      event.preventDefault()
+      await handleExternalDrop(sysPaths)
+      return
+    }
+  } catch { /* 剪贴板被占用等，回落图片粘贴 */ }
+
   const items = event.clipboardData?.items
   if (!items) return