feat(demo): add AppShellConfiguratorImpl for Vaadin 25 compatibility

Author: paodb

pom.xml

@@ -474,6 +474,7 @@
                                         <exclude>**/it/*</exclude>
                                         <exclude>**/DemoView.class</exclude>
                                         <exclude>**/DemoLayout.class</exclude>
+                                        <exclude>**/AppShellConfiguratorImpl.class</exclude>
                                     </excludes>
                                 </configuration>
                             </execution>

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

@@ -0,0 +1,28 @@
+/*-
+ * #%L
+ * Day of Week Selector Add-on
+ * %%
+ * Copyright (C) 2023 - 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.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * #L%
+ */
+package com.flowingcode.vaadin.addons;
+
+import com.vaadin.flow.component.page.AppShellConfigurator;
+import com.vaadin.flow.theme.Theme;
+
+@Theme
+public class AppShellConfiguratorImpl implements AppShellConfigurator {
+
+}