feat: implement clean global cross-organization permission node and backend service isolation logic

inventory-web/src/views/system/PermissionConfig.vue

@@ -203,9 +203,26 @@ const fetchTree = async () => {
   try {
     const res: any = await getAllPermissionTree()
     if (res.code === 200) {
-      rawTreeData.value = res.data
-      // 初始化表格结构（此时没有勾选状态）
-      tableData.value = transformData(res.data)
+      // --- 注入全局特权虚拟节点 ---
+      const globalNode = {
+        id: 99999, // 虚拟ID
+        name: '🌍 全局系统特权',
+        code: 'global_privileges',
+        type: 'menu',
+        children: [
+          {
+            id: 999991,
+            name: '跨组织/跨区域数据查询',
+            code: 'global:cross_company',
+            type: 'element'
+          }
+        ]
+      };
+      // 将虚拟节点放在最前面，然后交给 transformData 处理
+      const rawData = [globalNode, ...(res.data || [])];
+      
+      rawTreeData.value = rawData;
+      tableData.value = transformData(rawData);
     }
   } catch (e) {
     ElMessage.error('加载权限配置失败')