add alot

lib/services/pin_lock_service.dart

@@ -4,12 +4,9 @@ import 'dart:math';
 import 'package:crypto/crypto.dart';
 import 'package:flutter_secure_storage/flutter_secure_storage.dart';
 
-/// Stores and verifies a PIN. The raw PIN is never persisted — only a
-/// salted SHA-256 hash of it, kept in secure storage (Keychain on iOS,
-/// EncryptedSharedPreferences/Keystore on Android).
 class PinLockService {
   PinLockService({FlutterSecureStorage? storage})
-      : _storage = storage ?? const FlutterSecureStorage();
+    : _storage = storage ?? const FlutterSecureStorage();
 
   static const _saltKey = 'pin_salt';
   static const _hashKey = 'pin_hash';
@@ -53,4 +50,4 @@ class PinLockService {
     final bytes = utf8.encode('$salt:$pin');
     return sha256.convert(bytes).toString();
   }
-}
+}