implemented auth repository and service in dart (JWT)

backend-dart/lib/domain/repository/auth_repository.dart

@@ -0,0 +1,8 @@
+import 'package:backend_dart/domain/errors/error.dart';
+import 'package:fpdart/fpdart.dart';
+
+abstract class AuthRepository {
+  TaskEither<IError, String> generateToken(String userId);
+  TaskEither<IError, String> validateToken(String token);
+  TaskEither<IError, void> revokeToken(String token);
+}

backend-dart/lib/domain/repository/project_repository.dart

@@ -1,6 +1,6 @@
 import 'package:fpdart/fpdart.dart';
 import 'package:backend_dart/domain/entities/project.dart';
-import 'package:backend_dart/domain/interface/error.dart';
+import 'package:backend_dart/domain/errors/error.dart';
 
 abstract class ProjectRepository {
   /// Creates a new project.

backend-dart/lib/domain/repository/project_task_repository.dart

@@ -1,6 +1,6 @@
 import 'package:fpdart/fpdart.dart';
 import 'package:backend_dart/domain/entities/project_task.dart';
-import 'package:backend_dart/domain/interface/error.dart';
+import 'package:backend_dart/domain/errors/error.dart';
 
 abstract class ProjectTaskRepository {
   /// Creates a new project task.

backend-dart/lib/domain/repository/time_entry_repository.dart

@@ -1,6 +1,6 @@
 import 'package:fpdart/fpdart.dart';
 import 'package:backend_dart/domain/entities/time_entry.dart';
-import 'package:backend_dart/domain/interface/error.dart';
+import 'package:backend_dart/domain/errors/error.dart';
 
 abstract class TimeEntryRepository {
   /// Creates a new time entry.

backend-dart/lib/domain/repository/user_repository.dart

@@ -1,5 +1,5 @@
 import 'package:backend_dart/domain/entities/user.dart';
-import 'package:backend_dart/domain/interface/error.dart';
+import 'package:backend_dart/domain/errors/error.dart';
 import 'package:fpdart/fpdart.dart';
 
 abstract class UserRepository {