fix: The default for livereload in Spring Boot 4 RC1 is false (#22636)

Author: Artur-

vaadin-spring/src/main/java/com/vaadin/flow/spring/SpringDevToolsPortHandler.java

@@ -34,10 +34,9 @@ public class SpringDevToolsPortHandler implements EnvironmentPostProcessor {
     @Override
     public void postProcessEnvironment(ConfigurableEnvironment environment,
             SpringApplication application) {
-        // Only set the port if livereload is enabled (defaults to true when
-        // DevTools is present)
+        // Only set the port if livereload is enabled
         boolean liveReloadEnabled = environment.getProperty(
-                SPRING_DEVTOOLS_LIVERELOAD_ENABLED, Boolean.class, true);
+                SPRING_DEVTOOLS_LIVERELOAD_ENABLED, Boolean.class, false);
 
         if (!liveReloadEnabled) {
             return;

vaadin-spring/src/test/java/com/vaadin/flow/spring/SpringDevToolsPortHandlerTest.java

@@ -37,9 +37,9 @@ public void setUp() {
 
     @Test
     public void liveReloadEnabled_portIsAssigned() {
-        // Arrange: livereload enabled (default), no port set
+        // Arrange: livereload explicitly enabled, no port set
         Mockito.when(environment.getProperty(
-                "spring.devtools.livereload.enabled", Boolean.class, true))
+                "spring.devtools.livereload.enabled", Boolean.class, false))
                 .thenReturn(true);
         Mockito.when(environment.getProperty("spring.devtools.livereload.port"))
                 .thenReturn(null);
@@ -66,7 +66,7 @@ public void liveReloadEnabled_portIsAssigned() {
     public void liveReloadDisabled_portIsNotAssigned() {
         // Arrange: livereload explicitly disabled, no port set
         Mockito.when(environment.getProperty(
-                "spring.devtools.livereload.enabled", Boolean.class, true))
+                "spring.devtools.livereload.enabled", Boolean.class, false))
                 .thenReturn(false);
         Mockito.when(environment.getProperty("spring.devtools.livereload.port"))
                 .thenReturn(null);