Clear the cockpit glass for the Winners Circle

The six secondary displays sit over the viewscreen like the pod's bezels
and have nothing to say once the race is over. Worse, the radar sits dead
centre along the bottom edge - directly on top of the winner's spot, so
the one position that matters was the one you could not see.

They are hidden when the podium comes up, which uncovers the canvas the
3D is already being drawn on. No matching show: the mission is over by
then, and the next race builds a fresh cockpit.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

MUNGA_L4/L4MFDVIEW.h

@@ -71,6 +71,12 @@ public:
 	void
 		Resize(int display_width, int display_height);
 
+	// Take the pane off screen. Used for the Winners Circle, which wants
+	// the whole viewscreen: the panes overlap it like the pod's bezels,
+	// so hiding them uncovers the full canvas underneath.
+	void
+		Hide();
+
 	~MFDSplitView();
 
 	Logical