[Feat] Display a Confirmation Dialog Before Deleting a Task

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**Is your feature request related to a problem? Please describe.**
Accidentally deleting tasks can be frustrating for users. Currently, there is no confirmation step before a task is removed, increasing the risk of unintended deletions.

**Describe the solution you'd like**
When a user attempts to delete a task, a confirmation dialog should appear, asking the user to confirm or cancel the action. This dialog should display a message like:
"Are you sure you want to delete this task? This action cannot be undone."
The dialog should have two buttons:
Confirm/Delete: Deletes the task.
Cancel: Closes the dialog without deleting the task.

**Additional context**
The confirmation dialog should use a consistent design matching the app's theme (light/dark mode compatibility).
Ensure the dialog is accessible (e.g., proper text size and button focus states).

No files or tests are named. Start by locating the task deletion UI and its delete action, then determine how the app handles themed and accessible dialogs. Done means deletion requires an explicit confirmation, cancellation leaves the task intact, and the dialog supports light and dark themes with usable focus states.

Written by the indexing model from the issue text.