[az][gui] Responsivity issues in the UI when enabling/disabling zones

Describe the bug In the UI, when using the "Change zone availability" feature, if clicking randomly on the button multiple times, the toggle will either not move, or the UI will lock temporarily (waiting for daemon), or a grey widget will appear.

To Reproduce https://github.com/user-attachments/assets/49d67fa5-74bb-402a-9feb-f16c778e417f

Expected behavior Ideally, while the action is the toggles should enter a disabled state while the action is being executed, with a notif indicating that it's in progress. No broken widget should appear at any time.

Logs Please provide logs from the daemon, see Access logs on where to find them on your platform.

Additional info

• OS: Win 11 Pro
• CPU architecture or model: x64
• multipass version multipass 1.17.0-dev.ci6331+ga58dcf2e.win multipassd 1.17.0-dev.ci6331+ga58dcf2e.win

Additional context Add any other context about the problem here.