Add end-to-end tests for task assignment, modification, sorting, and child view updates

- Implement tests to verify that assigned titles display the correct child name in various chore and reward views.
- Create tests to ensure that child updates via SSE reflect correctly in the UI for task modifications, including point overrides and pending status resets.
- Add tests to validate the sorting order of tasks and rewards in both child and parent views, ensuring proper prioritization of pending, completed, and scheduled tasks.
- Introduce tests for scrolling behavior to ensure edited tasks are brought into view after modifications.

frontend/vue-app/e2e/mode_parent/task-activation/chore-activation.spec.ts

@@ -79,7 +79,7 @@ test.describe('Chore activation', () => {
       data: {
         mode: 'interval',
         interval_days: 1,
-        anchor_date: new Date().toISOString().slice(0, 10),
+        anchor_date: new Date().toLocaleDateString('en-CA'),
         interval_has_deadline: false,
       },
     })