Fix double-tap fullscreen gesture rotating on portrait videos

The fullscreen button routes through a portrait-video check (toggling
the details panel instead of rotating), but the double-tap gesture
called onToggleFullscreen directly and always rotated to landscape.
Extract the shared decision into PlayerControlsActions.performFullscreenTap()
and use it from both the button and the tap gesture handler.

Yattee/Views/Player/PlayerControlsView.swift

@@ -1220,8 +1220,8 @@ struct PlayerControlsView: View {
                 }
 
             case .toggleFullscreen:
-                // Execute immediately
-                onToggleFullscreen?()
+                // Execute immediately, using the same decision logic as the fullscreen button
+                controlsActions.performFullscreenTap()
 
             case .togglePiP:
                 // Execute immediately