fix: credentials not persisting on some devices

lib/core/providers/app_providers.dart

@@ -29,7 +29,20 @@ final sharedPreferencesProvider = Provider<SharedPreferences>((ref) {
 });
 
 final secureStorageProvider = Provider<FlutterSecureStorage>((ref) {
-  return const FlutterSecureStorage();
+  // Single, shared instance with explicit platform options
+  return const FlutterSecureStorage(
+    aOptions: AndroidOptions(
+      encryptedSharedPreferences: true,
+      sharedPreferencesName: 'conduit_secure_prefs',
+      preferencesKeyPrefix: 'conduit_',
+      // Avoid auto-wipe on transient errors; we handle errors in code
+      resetOnError: false,
+    ),
+    iOptions: IOSOptions(
+      accountName: 'conduit_secure_storage',
+      synchronizable: false,
+    ),
+  );
 });
 
 final storageServiceProvider = Provider<StorageService>((ref) {

lib/core/services/optimized_storage_service.dart

@@ -16,7 +16,7 @@ class OptimizedStorageService {
     required FlutterSecureStorage secureStorage,
     required SharedPreferences prefs,
   }) : _prefs = prefs,
-       _secureCredentialStorage = SecureCredentialStorage();
+       _secureCredentialStorage = SecureCredentialStorage(instance: secureStorage);
 
   // Optimized key names with versioning
   static const String _authTokenKey = 'auth_token_v3';

lib/core/services/secure_credential_storage.dart

@@ -8,8 +8,8 @@ import '../utils/debug_logger.dart';
 class SecureCredentialStorage {
   late final FlutterSecureStorage _secureStorage;
 
-  SecureCredentialStorage() {
-    _secureStorage = FlutterSecureStorage(
+  SecureCredentialStorage({FlutterSecureStorage? instance}) {
+    _secureStorage = instance ?? FlutterSecureStorage(
       aOptions: _getAndroidOptions(),
       iOptions: _getIOSOptions(),
     );
@@ -25,10 +25,8 @@ class SecureCredentialStorage {
       encryptedSharedPreferences: true,
       sharedPreferencesName: 'conduit_secure_prefs',
       preferencesKeyPrefix: 'conduit_',
-      resetOnError: true,
-      // Use more compatible encryption algorithms
-      keyCipherAlgorithm: KeyCipherAlgorithm.RSA_ECB_PKCS1Padding,
-      storageCipherAlgorithm: StorageCipherAlgorithm.AES_CBC_PKCS7Padding,
+      // Avoid auto-wipe on transient errors; handle gracefully in code
+      resetOnError: false,
     );
   }
 

lib/core/services/storage_service.dart

@@ -16,7 +16,7 @@ class StorageService {
     required SharedPreferences prefs,
   }) : _secureStorage = secureStorage,
        _prefs = prefs,
-       _secureCredentialStorage = SecureCredentialStorage();
+       _secureCredentialStorage = SecureCredentialStorage(instance: secureStorage);
 
   // Secure storage keys
   static const String _authTokenKey = 'auth_token';

lib/main.dart

@@ -29,7 +29,18 @@ void main() async {
   await SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);
 
   final sharedPrefs = await SharedPreferences.getInstance();
-  const secureStorage = FlutterSecureStorage();
+  const secureStorage = FlutterSecureStorage(
+    aOptions: AndroidOptions(
+      encryptedSharedPreferences: true,
+      sharedPreferencesName: 'conduit_secure_prefs',
+      preferencesKeyPrefix: 'conduit_',
+      resetOnError: false,
+    ),
+    iOptions: IOSOptions(
+      accountName: 'conduit_secure_storage',
+      synchronizable: false,
+    ),
+  );
 
   runApp(
     ProviderScope(