fix: 修复编辑对话框空白及双击编辑无效的问题

- PathEditDialog 添加 useEffect 在打开时同步 initialValue
- AppShell 添加 path-dblclick 事件监听，双击路径行打开编辑

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/components/dialogs/PathEditDialog.tsx

@@ -1,4 +1,4 @@
-import { useState } from 'react';
+import { useState, useEffect } from 'react';
 import { useTranslation } from 'react-i18next';
 
 interface PathEditDialogProps {
@@ -13,6 +13,13 @@ export function PathEditDialog({ open, title, initialValue, onConfirm, onCancel
   const { t } = useTranslation();
   const [value, setValue] = useState(initialValue);
 
+  // 每次打开时同步 initialValue（解决 React 复用实例导致空白的问题）
+  useEffect(() => {
+    if (open) {
+      setValue(initialValue);
+    }
+  }, [open, initialValue]);
+
   if (!open) return null;
 
   return (