Differentiate the main UTM window title from VM windows

[conath]

After clicking Play to run a VM on macOS, the main UTM window and the VM's window have the same title:

This is confusing when trying to switch between them using the menu bar item "Window".
The VM and main windows should each gain additional text to indicate which one is which. For example, the VM window could indicate the state of the VM ("Windows 10 installed – running").

[JaiganeshKumaran]

I think it's better to keep the title of the main window as UTM instead of the selected VM's name.

[conath]

I've gotten this to work by removing the navigationTitle from the VMDetailsView. However this creates a UX problem: now the title of the toolbar doesn't show the name of the selected VM anymore.

There needs to be a way to keep the window title from changing while still showing the name of the selected VM. Alternatively, the details screen could be redesigned to show the name on macOS. @osy what to you think?

[conath]

Or maybe UTM could be changed to have a Window menu similar to Messages, where the main window is always listed separately from any conversation windows.

[osy]

Fixed with #3125