Represents the label of the screen, which serves as its title. The title is normally displayed as part of the navigation bar.
If this property is not set, it returns the title set for this screen in Calcapp Creator.
Sets the screen label to "Equipment" if Field1 (which is part of the form screen MainScreen) is valid (by consulting its Valid property). If Field1 is not valid, the screen label is set to "Equipment ⚠️" (with a warning triangle).