feat: finish unread update triage offline (#351)

frontend/index.html

@@ -533,6 +533,7 @@
 <script src="static/background-issue-sync.js"></script>
 <script src="static/issue-outbox.js"></script>
 <script src="static/authored-outbox.js"></script>
+<script src="static/notification-read-outbox.js"></script>
 <script src="static/offline-work.js"></script>
 <script src="static/offline-today.js"></script>
 <script src="static/my-work.js"></script>