Allow automatically shutting down VMs that have active tray icons

[Atrate]

How to file a helpful issue

The problem you're addressing (if any)

It seems that qubes-app-shutdown-idle has two considerations as to when shutdown a qube:

1. Active windows (including tray icons).
2. Active downlink interfaces (for sys-* qubes)

The fact that qubes-app-shutdown-idle does not shut down a qube when a tray icon is active means that if I have a sys-vpn qube that creates a nm_applet tray icon, it will never shut down, even if no qubes are using it anymore for network access.

The solution you'd like

Another checkbox in qube-manager or way to configure qubes-app-shutdown-idle so that if ignores tray icons when deciding which vms to shut down automatically.

The value to a user, and who that user might be

That user: me, and certainly many others. I'd like my additional sys-vpn qubes to shut down when they are not being used, but the network manager tray icon is seemingly preventing that.

Related issues

#832, #912

Completion criteria checklist

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