try to fix secure storage issues

ref #523

android/app/src/main/AndroidManifest.xml

@@ -1,5 +1,13 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android">
-    <application android:label="Waterfly III" android:name="${applicationName}" android:icon="@mipmap/ic_launcher" android:enableOnBackInvokedCallback="true" android:usesCleartextTraffic="true" android:networkSecurityConfig="@xml/network_security_config">
+
+    <application
+        android:name="${applicationName}"
+        android:enableOnBackInvokedCallback="true"
+        android:fullBackupContent="@xml/backup_rules"
+        android:icon="@mipmap/ic_launcher"
+        android:label="Waterfly III"
+        android:networkSecurityConfig="@xml/network_security_config"
+        android:usesCleartextTraffic="true">
         <activity android:name=".MainActivity" android:exported="true" android:launchMode="singleTop" android:taskAffinity="" android:theme="@style/LaunchTheme" android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode" android:hardwareAccelerated="true" android:windowSoftInputMode="adjustResize">
             <!-- Specifies an Android theme to apply to this Activity as soon as
                  the Android process has started. This theme is visible to the user

android/app/src/main/res/xml/backup_rules.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8"?>
+<full-backup-content>
+    <exclude
+        domain="sharedpref"
+        path="FlutterSecureStorage" />
+</full-backup-content>

lib/auth.dart

@@ -242,7 +242,9 @@ class FireflyService with ChangeNotifier {
   late TimeZoneHandler tzHandler;
 
   final FlutterSecureStorage storage = const FlutterSecureStorage(
-    aOptions: AndroidOptions(),
+    aOptions: AndroidOptions(
+      resetOnError: true,
+    ),
   );
 
   final Logger log = Logger("Auth.FireflyService");