Implement E2EE and message content moderation

apps/mobile/src/polyfills/crypto.ts

@@ -0,0 +1,32 @@
+/**
+ * Crypto polyfill for React Native
+ * 
+ * This file must be imported BEFORE any code that uses crypto.
+ * It installs react-native-quick-crypto as the global crypto implementation.
+ * 
+ * On web, we skip this since the native Web Crypto API is available.
+ */
+
+import { Platform } from 'react-native';
+
+if (Platform.OS !== 'web') {
+  try {
+    // Import react-native-quick-crypto to install its polyfill
+    const QuickCrypto = require('react-native-quick-crypto');
+    
+    // Install the polyfill globally if not already present
+    if (typeof global.crypto === 'undefined') {
+      (global as any).crypto = QuickCrypto;
+    }
+    
+    // Also ensure subtle is available
+    if (global.crypto && !global.crypto.subtle) {
+      (global.crypto as any).subtle = QuickCrypto.subtle;
+    }
+    
+    console.log('[Crypto] react-native-quick-crypto polyfill installed');
+  } catch (error) {
+    console.error('[Crypto] Failed to install crypto polyfill:', error);
+    console.error('[Crypto] Make sure you have run: npx expo prebuild --clean');
+  }
+}