Add extended PaperServerListPingEvent

Add a new event that extends the original ServerListPingEvent
and allows full control of the response sent to the client.

paper-api/src/main/java/org/bukkit/event/server/ServerListPingEvent.java

@@ -248,9 +248,11 @@ public class ServerListPingEvent extends ServerEvent implements Iterable<Player>
      *
      * @throws UnsupportedOperationException if the caller of this event does
      *     not support removing players
+     * @deprecated the Iterable interface will be removed at some point
      */
     @NotNull
     @Override
+    @Deprecated(forRemoval = true, since = "1.20.6")
     public Iterator<Player> iterator() throws UnsupportedOperationException {
         throw new UnsupportedOperationException();
     }

paper-api/src/main/java/org/bukkit/util/CachedServerIcon.java

@@ -18,4 +18,9 @@ public interface CachedServerIcon {
     @Nullable
     public String getData(); // Paper
 
+    // Paper start
+    default boolean isEmpty() {
+        return getData() == null;
+    }
+    // Paper end
 }