fix: Handle empty message content for thread titles

Ensures a fallback thread title is provided when the original message content is empty.
The thread title will now default to the message author's name in such cases,
preventing empty or uninformative thread titles.

Author: billpapat

application/src/main/java/org/togetherjava/tjbot/features/basic/SuggestionsUpDownVoter.java

@@ -55,19 +55,26 @@ public void onMessageReceived(MessageReceivedEvent event) {
     }
 
     private static void createThread(Message message) {
-        String title = message.getContentRaw();
 
-        if (title.length() >= TITLE_MAX_LENGTH) {
-            int lastWordEnd = title.lastIndexOf(' ', TITLE_MAX_LENGTH);
+        String threadTitle;
+        String messageContent = message.getContentRaw();
+
+        if (messageContent.isEmpty()){
+            threadTitle = message.getAuthor().getName();
+        } else if (messageContent.length() >= TITLE_MAX_LENGTH) {
+            int lastWordEnd = messageContent.lastIndexOf(' ', TITLE_MAX_LENGTH);
 
             if (lastWordEnd == -1) {
                 lastWordEnd = TITLE_MAX_LENGTH;
             }
 
-            title = title.substring(0, lastWordEnd);
+            threadTitle = messageContent.substring(0, lastWordEnd);
+        } else {
+
+            threadTitle = messageContent;
         }
 
-        message.createThreadChannel(title).queue();
+        message.createThreadChannel(threadTitle).queue();
     }
 
     private static void reactWith(String emojiName, Emoji fallbackEmoji, Guild guild,