added project model

lib/features/common/bloc/project_cubit.dart

@@ -0,0 +1,19 @@
+import 'package:flutter_bloc/flutter_bloc.dart';
+import 'package:flutter_secure_storage/flutter_secure_storage.dart';
+
+class ProjectCubit extends Cubit<String?> {
+  final FlutterSecureStorage storage;
+  static const String projectKey = "selected_project_uuid";
+
+  ProjectCubit(this.storage) : super(null);
+
+  Future<void> setProjectUUID(String newUUID) async {
+    await storage.write(key: projectKey, value: newUUID);
+    emit(newUUID);
+  }
+
+  Future<void> clearProjectUUID() async {
+    await storage.delete(key: projectKey);
+    emit(null);
+  }
+}