feat: added authentification and redirection

lib/ui/auth/viewmodel/login_view_model.dart

@@ -0,0 +1,24 @@
+import 'package:flutter/material.dart';
+import 'package:seshat/data/repositories/auth_repository.dart';
+import 'package:seshat/utils/command.dart';
+import 'package:seshat/utils/result.dart';
+
+class LoginViewModel extends ChangeNotifier {
+  LoginViewModel({required AuthRepository authRepository})
+    : _authRepository = authRepository {
+    login = Command1<void, (String username, String password)>(_login);
+  }
+
+  final AuthRepository _authRepository;
+
+  late Command1 login;
+
+  Future<Result<void>> _login((String, String) credentials) async {
+    final (username, password) = credentials;
+    final result = await _authRepository.login(username, password);
+    if (result is Error<void>) {
+      debugPrint("Hehe no");
+    }
+    return result;
+  }
+}