feat(01-06): create password update page with validation

- Implemented UpdatePasswordPage with password strength indicator
- Added password validation utility with comprehensive checks
- Enhanced AuthProvider with updatePasswordFromReset method
- Extended AuthRepository interface and implementation for password reset
- Added InvalidTokenException to auth exception hierarchy
- Includes accessibility features and error handling
- Password strength indicator with real-time feedback

Files:
- lib/features/authentication/presentation/pages/update_password_page.dart
- lib/core/utils/password_validator.dart
- lib/providers/auth_provider.dart
- lib/features/authentication/domain/repositories/auth_repository.dart
- lib/features/authentication/data/repositories/auth_repository_impl.dart
- lib/core/errors/auth_exceptions.dart

lib/core/errors/auth_exceptions.dart

@@ -120,6 +120,19 @@ class EmailNotVerifiedException extends AuthException {
         );
 }
 
+/// Exception thrown when a reset token is invalid or expired
+class InvalidTokenException extends AuthException {
+  const InvalidTokenException({
+    String message = 'Reset token is invalid or has expired',
+    String? code,
+    dynamic originalError,
+  }) : super(
+          message: message,
+          code: code ?? 'INVALID_TOKEN',
+          originalError: originalError,
+        );
+}
+
 /// Exception thrown when too many login attempts are made
 class TooManyRequestsException extends AuthException {
   const TooManyRequestsException({
@@ -198,6 +211,17 @@ class AuthExceptionFactory {
       );
     }
     
+    if (lowerMessage.contains('invalid token') ||
+        lowerMessage.contains('token expired') ||
+        lowerMessage.contains('reset token') ||
+        lowerMessage.contains('session has expired')) {
+      return InvalidTokenException(
+        message: _extractUserFriendlyMessage(errorMessage) ?? 'Reset token is invalid or has expired',
+        code: errorCode,
+        originalError: error,
+      );
+    }
+    
     if (lowerMessage.contains('user not found') ||
         lowerMessage.contains('no user found') ||
         lowerMessage.contains('user does not exist')) {