libui: Properly request redraws from the server

Before this, the call to update() was always skipped.

libui/src/Window.cpp

@@ -75,7 +75,7 @@ namespace ui
     Result<void> Window::draw()
     {
         m_canvas.fill(m_background);
-        if (m_main_widget) return m_main_widget->draw(m_canvas);
+        if (m_main_widget) TRY(m_main_widget->draw(m_canvas));
         update();
         return {};
     }