made use of first class citizen objects as json validator functions

backend-dart/lib/application/repository/project_repository_impl.dart

@@ -27,7 +27,7 @@ class ProjectRepositoryImpl implements ProjectRepository {
   }
 
   @override
-  TaskEither<IError, void> delete(String id) {
+  TaskEither<IError, Project> delete(String id) {
     return database.projects.delete(id);
   }
 

backend-dart/lib/application/repository/project_task_repository_impl.dart

@@ -32,7 +32,7 @@ class ProjectTaskRepositoryImpl implements ProjectTaskRepository {
   }
 
   @override
-  TaskEither<IError, void> delete(String id) {
+  TaskEither<IError, ProjectTask> delete(String id) {
     return database.tasks.delete(id);
   }
 

backend-dart/lib/application/repository/time_entry_repository_impl.dart

@@ -37,7 +37,7 @@ class TimeEntryRepositoryImpl implements TimeEntryRepository {
   }
 
   @override
-  TaskEither<IError, void> delete(String id) {
+  TaskEither<IError, TimeEntry> delete(String id) {
     return database.timeEntries.delete(id);
   }
 

backend-dart/lib/application/repository/user_repository_impl.dart

@@ -34,7 +34,7 @@ class UserRepositoryImpl implements UserRepository {
   }
 
   @override
-  TaskEither<IError, void> delete(String id) {
+  TaskEither<IError, User> delete(String id) {
     return database.users.delete(id);
   }