chore: export and import components through `component/index.js`

src/App.js

@@ -1,8 +1,7 @@
 import React from 'react';
 import {StyleSheet, View, Platform} from 'react-native';
 import {StatusBarHeight} from './api/StatusBarHeight';
-import YooLogin from './component/YooLogin';
+import {YooLogin, YooBackground} from './component/index';
-import {YooBackground} from './ui/YooBackground';
 
 const styles = StyleSheet.create({
   container: {

src/component/index.js

@@ -0,0 +1,4 @@
+import YooLogin from './YooLogin';
+import YooBackground from '../ui/YooBackground';
+
+export {YooLogin, YooBackground};