Fix up the system tray icon(s)

pubspec.yaml

@@ -62,6 +62,7 @@ flutter:
 
   # To add assets to your application, add an assets section, like this:
   assets:
+    - assets/ # Include the main assets directory for the icon
     - assets/sounds/
   #   - images/a_dot_burr.jpeg
   #   - images/a_dot_ham.jpeg