refactor(task-management): update search handling and improve task filtering

- Modified search handling to utilize the taskManagement slice for consistent state management across components.
- Enhanced placeholder text in search filters for better user guidance.
- Updated task fetching logic to ensure accurate search value retrieval from the correct state slice.

worklenz-backend/src/controllers/tasks-controller-v2.ts

@@ -109,7 +109,7 @@ export default class TasksControllerV2 extends TasksControllerBase {
   }
 
   private static getQuery(userId: string, options: ParsedQs) {
-    const searchField = options.search ? "t.name" : "sort_order";
+    const searchField = options.search ? ["t.name", "CONCAT((SELECT key FROM projects WHERE id = t.project_id), '-', task_no)"] : "sort_order";
     const { searchQuery, sortField } = TasksControllerV2.toPaginationOptions(options, searchField);
 
     const isSubTasks = !!options.parent_task;