fix(mobile): defer crypto backend init into AppBootstrap (prevents white-screen)

apps/mobile/app/_layout.tsx

@@ -1,34 +1,33 @@
-import { crypto } from '@chat-app/shared';
 import { Stack } from 'expo-router';
 import { StatusBar } from 'expo-status-bar';
 import { GestureHandlerRootView } from 'react-native-gesture-handler';
 import { SafeAreaProvider } from 'react-native-safe-area-context';
 
+import { AppBootstrap } from '../components/AppBootstrap';
 import { ErrorBoundary } from '../components/ErrorBoundary';
 import { IncomingCallModal } from '../components/IncomingCallModal';
 import { AuthProvider } from '../lib/authContext';
 import { CallProvider } from '../lib/callContext';
-import { createLibsodiumBackend } from '../lib/cryptoBackend';
-
-crypto.setCryptoBackend(createLibsodiumBackend());
 
 export default function RootLayout() {
   return (
     <GestureHandlerRootView style={{ flex: 1 }}>
       <SafeAreaProvider>
-        <ErrorBoundary>
-          <AuthProvider>
-            <CallProvider>
-              <StatusBar style="auto" />
-              <Stack screenOptions={{ headerShown: false }}>
-                <Stack.Screen name="index" />
-                <Stack.Screen name="(app)" />
-                <Stack.Screen name="auth/callback" />
-              </Stack>
-              <IncomingCallModal />
-            </CallProvider>
-          </AuthProvider>
-        </ErrorBoundary>
+        <AppBootstrap>
+          <ErrorBoundary>
+            <AuthProvider>
+              <CallProvider>
+                <StatusBar style="auto" />
+                <Stack screenOptions={{ headerShown: false }}>
+                  <Stack.Screen name="index" />
+                  <Stack.Screen name="(app)" />
+                  <Stack.Screen name="auth/callback" />
+                </Stack>
+                <IncomingCallModal />
+              </CallProvider>
+            </AuthProvider>
+          </ErrorBoundary>
+        </AppBootstrap>
       </SafeAreaProvider>
     </GestureHandlerRootView>
   );