Add TaskResponse model to encapsulate tasks and pagination data

This commit introduces a new class called TaskResponse, which holds both the tasks and pagination information returned from the API. The class includes a factory constructor to create an instance from JSON data, ensuring that the API response is neatly packaged into an easily manageable object. This enhances code readability and maintainability.

- Create a TaskResponse class with tasks and pagination fields
- Add a factory constructor for JSON to TaskResponse conversion

lib/models/task_response.dart

@@ -0,0 +1,19 @@
+import 'package:auto_gpt_flutter_client/models/pagination.dart';
+import 'package:auto_gpt_flutter_client/models/task.dart';
+
+class TaskResponse {
+  final List<Task> tasks;
+  final Pagination pagination;
+
+  TaskResponse({required this.tasks, required this.pagination});
+
+  factory TaskResponse.fromJson(Map<String, dynamic> json) {
+    return TaskResponse(
+      tasks: (json['tasks'] as List).map((taskJson) {
+        var task = Task.fromMap(taskJson);
+        return task;
+      }).toList(),
+      pagination: Pagination.fromJson(json['pagination']),
+    );
+  }
+}