Do not serialize intermediate server attributes

php/utils/servers-rooms.php

@@ -598,7 +598,10 @@
 		 * Return information for JSON serialization.
 		 */
 		function jsonSerialize(): array {
-			return get_object_vars($this);
+			$details = get_object_vars($this);
+			unset($details['room_hints']);
+			unset($details['merge_error']);
+			return $details;
 		}
 
 		/**