enhance(mobile): exit animation for android

android/app/src/main/java/com/logseq/app/MainActivity.java

@@ -10,4 +10,10 @@ public class MainActivity extends BridgeActivity {
         super.onCreate(savedInstanceState);
         registerPlugin(FolderPicker.class);
     }
+
+    @Override
+    public void onPause() {
+        overridePendingTransition(0, R.anim.byebye);
+        super.onPause();
+    }
 }

android/app/src/main/res/anim/byebye.xml

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+
+<set xmlns:android="http://schemas.android.com/apk/res/android"
+    android:zAdjustment="top">
+    <translate android:fromYDelta="0" android:toYDelta="5%p"
+        android:duration="250"
+        android:interpolator="@android:interpolator/fast_out_slow_in"/>
+    <alpha android:fromAlpha="1.0" android:toAlpha="0.0"
+        android:fillEnabled="true" android:fillBefore="true" android:fillAfter="true"
+        android:startOffset="100" android:duration="150"
+        android:interpolator="@android:interpolator/fast_out_slow_in" />
+</set>