Fix ticket page 500 from unbounded audit timeline (#112)

A ticket updated by hwmonDaemon had ~52k audit rows; getTicketTimeline()
loaded all of them and exhausted PHP's 128MB memory limit, so the ticket
page returned 500. Not related to the MCP server.

- getTicketTimeline() takes a limit (newest first). The ticket page shows
  the latest 500 events with a note when older ones are omitted; the JSON
  export caps at 5000.
- create_ticket_api.php: the description is refreshed on every run, and
  that alone wrote a reason-only audit row every few minutes per open
  ticket. Audit only real title/priority changes.
- create_ticket_api.php: after creating a brand-new ticket the dedup retry
  loop fell through into a second iteration on a closed connection,
  appending a 500 error body after the success response. Exit instead.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MGDKHiU5RJdo3dqQUDow3X

views/TicketView.php

@@ -819,6 +819,9 @@ document.addEventListener('DOMContentLoaded', function() {
             </div>
           <?php endforeach ?>
         </div>
+            <?php if (!empty($timelineTruncated)) : ?>
+          <div class="lt-empty lt-text-xs">Showing the <?= count($timeline) ?> most recent events; older activity is in the audit log.</div>
+            <?php endif ?>
       <?php endif ?>
     </div>
   </div>