feat(demo): add support for dynamic theme switching

Author: javier-godoy

src/test/java/com/flowingcode/vaadin/addons/AppShellConfiguratorImpl.java

@@ -2,7 +2,7 @@
  * #%L
  * Upload Helper Add-on
  * %%
- * Copyright (C) 2022 - 2024 Flowing Code
+ * Copyright (C) 2022 - 2026 Flowing Code
  * %%
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,11 +19,20 @@
  */
 package com.flowingcode.vaadin.addons;
 
+import com.flowingcode.vaadin.addons.demo.DynamicTheme;
 import com.vaadin.flow.component.page.AppShellConfigurator;
 import com.vaadin.flow.component.page.Push;
+import com.vaadin.flow.server.AppShellSettings;
 
 @SuppressWarnings("serial")
 @Push
 public class AppShellConfiguratorImpl implements AppShellConfigurator {
 
+  @Override
+  public void configurePage(AppShellSettings settings) {
+    if (DynamicTheme.isFeatureSupported()) {
+      DynamicTheme.LUMO.initialize(settings);
+    }
+  }
+
 }