refactor(screens): 修改 MainViewScreen 组件的导出名称- 将 WebViewScreen 函数重命名为 MainViewScreen，以匹配文件名和组件名

src/app/screens/main/MainViewScreen.tsx

@@ -17,7 +17,7 @@ import UpdateManager from '../../../../specs/NativeUpdateManager.ts';
 import Spinner from '@common/components/Spinner.tsx';
 import RNFS from 'react-native-fs';
 
-export default function WebViewScreen() {
+export default function MainViewScreen() {
   const [progress, setProgress] = useState('');
   const [progressH, setProgressH] = useState('');
   const [isLoading, setLoading] = useState(false);