[FEATURE]: (app) show queued messages

[neriousy]

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

The UI should show which messages are queued just like it is in the TUI

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• feat(app): queued message controls with send now in prompt #12707: Very similar request — specifically about showing queued messages in the app/desktop UI with controls (overlaps closely with this issue's scope)
• [FEATURE]: Better controls/UX for queued messages. #8685: Related request for better UX/controls for queued messages in the app

Please review these issues and consider whether your request is already covered before we proceed.