feat: clear MMKV on fresh install

Author: MarioAslau

app/components/Nav/App/App.tsx

@@ -34,7 +34,7 @@ import {
   EXISTING_USER,
   LAST_APP_VERSION,
 } from '../../../constants/storage';
-import { getVersion } from 'react-native-device-info';
+import { getVersion, getFirstInstallTime, getLastUpdateTime } from 'react-native-device-info';
 import { Authentication } from '../../../core/';
 import Device from '../../../util/device';
 import SDKConnect from '../../../core/SDKConnect/SDKConnect';
@@ -922,6 +922,15 @@ const App: React.FC = () => {
 
   useEffect(() => {
     async function startApp() {
+      const firstInstallTime = await getFirstInstallTime();
+      const lastUpdateTime = await getLastUpdateTime();
+      const isFreshInstall = firstInstallTime === lastUpdateTime;
+      
+      if (isFreshInstall) {
+        // Clear all MMKV storage on fresh install to avoid leftovers of EXISTING_USER in case of phone migration
+        await StorageWrapper.clearAll();
+      }
+
       const existingUser = await StorageWrapper.getItem(EXISTING_USER);
       if (!existingUser) {
         // List of chainIds to add (as hex strings)