Add executable setting to minimize MO2 to the system tray while running

[JonathanFeenstra]

This adds a checkbox to the executables window to minimize Mod Organizer to the system tray while the executable is running. It will automatically reappear after it finishes running, or if the user clicks on the system tray icon while it's still running. Closes #2119.

[Holt59]

I'm okay with the idea but maybe this could be isolated in a dedicated class to 1) avoid adding more clutter to MainWindow and 2) allow us to add more stuff to the tray icon in the future and keep them in a single location.

[JonathanFeenstra]

I could move the code from MainWindow::createSystemTrayIcon to the constructor of a new QSystemTrayIcon subclass, would that be enough? minimizeToSystemTray and restoreFromSystemTray are really tied to the MainWindow, so I don't think those can easily be separated.

[Holt59]

I could move the code from MainWindow::createSystemTrayIcon to the constructor of a new QSystemTrayIcon subclass, would that be enough? minimizeToSystemTray and restoreFromSystemTray are really tied to the MainWindow, so I don't think those can easily be separated.

I don't think you need to subclass QSystemTrayIcon, having some kind of "system tray manager" class with a tray icon has an attribute should be enough. For the minimizeToSystemTray and restoreFromSystemTray, you can probably move them by passing the main window to the new class?

[JonathanFeenstra]

Yes, that seems to work. I also passed the log dock widget because it can be in a separate floating window which should also be minimized to the tray.

[Holt59]

Is there any reason not to initialize m_SystemTrayIcon in the constructor? This would avoid a lot of check everywhere, and would remove the need for a custom destructor since Qt's ownership would delete the object for us.

[JonathanFeenstra]

Not really, I'll initialize it in the constructor to simplify the code.

[Holt59]

Can you merge or rebase from master to fix the CI build?