fix: handling of surface action

cosmic-applet-input-sources/src/lib.rs

@@ -189,7 +189,11 @@ impl cosmic::Application for Window {
                     }
                 }
             }
-            Message::Surface(surface_message) => unreachable!(),
+            Message::Surface(a) => {
+                return cosmic::task::message(cosmic::Action::Cosmic(
+                    cosmic::app::Action::Surface(a),
+                ));
+            }
         }
 
         Task::none()