Bump chat.js cache version

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/static/dashboard.html

@@ -765,7 +765,7 @@
     <script src="/static/js/network-graph.js?v=20260316a"></script>
     <script src="/static/js/app_network.js?v=20260316a"></script>
     <script src="/static/js/tutorial.js?v=20260316e"></script>
-    <script src="/static/js/chat.js?v=20260316e"></script>
+    <script src="/static/js/chat.js?v=20260316f"></script>
     <script>document.addEventListener("DOMContentLoaded",function(){Chat.init();Tutorial.init()});</script>
 
     <!-- Map Fullscreen Overlay -->