[chromecast] Do not cast the background discovery setting to String

The value comes back as a Boolean when the setting is written via REST, so
@Modified throws ClassCastException, SCR swallows it and background discovery
keeps running while the config reads as false. Accept either type, and make the
field volatile since it is read from the discovery threads.

Signed-off-by: Jason Hubbard <jasonahubbard@gmail.com>

Author: jahubba

bundles/org.openhab.binding.chromecast/src/main/java/org/openhab/binding/chromecast/internal/discovery/ChromecastDiscoveryParticipant.java

@@ -54,7 +54,7 @@ public class ChromecastDiscoveryParticipant implements MDNSDiscoveryParticipant
     private static final String PROPERTY_DEVICE_ID = "id";
     private static final String SERVICE_TYPE = "_googlecast._tcp.local.";
 
-    private boolean isAutoDiscoveryEnabled = true;
+    private volatile boolean isAutoDiscoveryEnabled = true;
 
     @Activate
     protected void activate(ComponentContext componentContext) {
@@ -68,10 +68,17 @@ protected void modified(ComponentContext componentContext) {
 
     private void activateOrModifyService(ComponentContext componentContext) {
         Dictionary<String, @Nullable Object> properties = componentContext.getProperties();
-        String autoDiscoveryPropertyValue = (String) properties
-                .get(DiscoveryService.CONFIG_PROPERTY_BACKGROUND_DISCOVERY);
-        if (autoDiscoveryPropertyValue != null && !autoDiscoveryPropertyValue.isBlank()) {
-            isAutoDiscoveryEnabled = Boolean.valueOf(autoDiscoveryPropertyValue);
+        Object autoDiscoveryPropertyValue = properties.get(DiscoveryService.CONFIG_PROPERTY_BACKGROUND_DISCOVERY);
+        // Do not cast to String: the value arrives as a Boolean when the setting is written through
+        // the REST API (or any JSON-typed config source), and a ClassCastException thrown out of
+        // @Modified is swallowed by SCR - leaving background discovery silently still enabled.
+        if (autoDiscoveryPropertyValue instanceof Boolean booleanValue) {
+            isAutoDiscoveryEnabled = booleanValue;
+        } else if (autoDiscoveryPropertyValue != null) {
+            String value = autoDiscoveryPropertyValue.toString();
+            if (!value.isBlank()) {
+                isAutoDiscoveryEnabled = Boolean.parseBoolean(value);
+            }
         }
     }