TF-571 Add Account Repository to manage accounts

lib/features/login/data/datasource/account_datasource.dart

@@ -0,0 +1,7 @@
+import 'package:model/account/account.dart';
+
+abstract class AccountDatasource {
+  Future<Account> getCurrentAccount();
+
+  Future<void> setCurrentAccount(Account newCurrentAccount);
+}

lib/features/login/domain/repository/account_repository.dart

@@ -0,0 +1,8 @@
+
+import 'package:model/account/account.dart';
+
+abstract class AccountRepository {
+  Future<Account> getCurrentAccount();
+
+  Future<void> setCurrentAccount(Account newCurrentAccount);
+}