filtered deleted messages from search and chat view, refactored chat bubble styling for deleted comments, and updated tests

lib/view/pages/talk/data/chat_search_controller.dart

@@ -21,6 +21,7 @@ class ChatSearchController {
     for (final element in response.sortByTimestamp()) {
       if (element.systemMessage.contains('reaction')) continue;
       if (element.systemMessage.contains('poll_voted')) continue;
+      if (element.systemMessage.contains('message_deleted')) continue;
 
       final haystackText = RichObjectStringProcessor.parseToString(
         element.message,