refactor: 完全移除错误添加的 AboutPage 和相关引用

- 删除 src/pages/AboutPage/ 目录和文件
- 从 App.tsx 移除 AboutPage 导入和使用
- 从 TabType 移除 'about' 类型
- 从 AppSidebar 移除"关于"菜单项
- 删除未使用的 Info 图标导入

Author: jsrcode

src/App.tsx

@@ -13,7 +13,6 @@ import { SettingsPage } from '@/pages/SettingsPage';
 import { TransparentProxyPage } from '@/pages/TransparentProxyPage';
 import { ToolManagementPage } from '@/pages/ToolManagementPage';
 import { HelpPage } from '@/pages/HelpPage';
-import { AboutPage } from '@/pages/AboutPage';
 import { useToast } from '@/hooks/use-toast';
 import { useAppEvents } from '@/hooks/useAppEvents';
 import { useCloseAction } from '@/hooks/useCloseAction';
@@ -46,8 +45,7 @@ type TabType =
   | 'transparent-proxy'
   | 'provider-management'
   | 'settings'
-  | 'help'
-  | 'about';
+  | 'help';
 
 function App() {
   const { toast } = useToast();
@@ -397,15 +395,6 @@ function App() {
           )}
           {activeTab === 'provider-management' && <ProviderManagementPage />}
           {activeTab === 'help' && <HelpPage onShowOnboarding={handleShowOnboarding} />}
-          {activeTab === 'about' && (
-            <AboutPage
-              updateInfo={updateInfo}
-              onUpdateCheck={() => {
-                setUpdateInfo(null);
-                setIsUpdateDialogOpen(true);
-              }}
-            />
-          )}
         </main>
 
         {/* 更新对话框 */}

src/components/layout/AppSidebar.tsx

@@ -16,7 +16,6 @@ import {
   Sun,
   Moon,
   Monitor,
-  Info,
   //预留
   // User,
 } from 'lucide-react';
@@ -54,7 +53,6 @@ const secondaryItems = [
   { id: 'provider-management', label: '供应商', icon: Building2 },
   { id: 'help', label: '帮助', icon: HelpCircle },
   { id: 'settings', label: '设置', icon: SettingsIcon },
-  { id: 'about', label: '关于', icon: Info },
 ];
 
 export function AppSidebar({