feat: 优化前端导航和后端服务

- 更新侧边栏导航
- 优化 MCP 页面
- 调整 model service

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

web/src/views/MCP.vue

@@ -1150,8 +1150,16 @@ const statusClass = (status: string) => {
                         <i class="fa-solid fa-trash text-xs"></i>
                       </button>
                     </div>
-                    <!-- 文件夹内新建文件/上传按钮 -->
+                    <!-- 文件夹内新建文件夹/文件/上传按钮 -->
                     <div class="flex items-center gap-2 px-2 py-1">
+                      <button
+                        @click.stop="showNewFolderInput(folder.id)"
+                        class="flex items-center gap-1 text-xs text-gray-500 hover:text-white transition-colors opacity-0 group-hover:opacity-100"
+                        title="New Folder"
+                      >
+                        <i class="fa-solid fa-folder-plus"></i>
+                        <span>New Folder</span>
+                      </button>
                       <button
                         @click.stop="showNewFileInput(folder.id)"
                         class="flex items-center gap-1 text-xs text-gray-500 hover:text-white transition-colors opacity-0 group-hover:opacity-100"