Esc in /tasks overlay also dismisses active question prompt #3430

Describe the bug

When the Copilot CLI /tasks overlay is open and the agent asks a question, pressing Esc to close the task/subagent menu also affects the underlying question prompt.

The same Esc keypress appears to be handled twice:

1. It closes the /tasks overlay.
2. It also dismisses or skips the active question prompt underneath.

This prevents the user from answering the question and can cause the agent to continue with an unintended skipped/default response.

This seems inconsistent with the documented Esc behavior for Copilot CLI, where an open dialog, overlay, or picker should be closed before Esc acts as a broader cancel action.

References:

• /tasks command reference
• Esc behavior in Copilot CLI
• /fleet and subagent task execution

Affected version

GitHub Copilot CLI 1.0.49.

Steps to reproduce the behavior

1. Start an interactive Copilot CLI session.
2. Start a task that uses subagents or background tasks.
3. Open the task/subagent manager with /tasks.
4. While the /tasks overlay is open, wait for the agent to ask a question or clarification.
5. Press Esc once, intending only to close the /tasks overlay.
6. Observe that the active question is also skipped or dismissed.

Expected behavior

Pressing Esc while the /tasks overlay is open should only close that overlay and return focus to the active question prompt.

The question should remain visible and answerable.

Additional context

This looks like a key handling or focus propagation issue. The /tasks overlay appears not to consume the Esc event after using it to close itself, so the same keypress reaches the global cancel handler or the underlying question UI.

A possible fix would be to make the /tasks overlay treat Esc as handled when it closes the overlay, preventing the key event from being forwarded to lower-priority UI layers.

A regression test could cover this stacked UI case:

1. An active question prompt is visible underneath the /tasks overlay.
2. The user presses Esc once.
3. Only the /tasks overlay closes.
4. The question prompt remains open and answerable.