hardening: 20s client timeout on API GETs

A hung read can no longer stall the recon/pineap poll loops (AbortController).
Writes keep no client abort: radio deploys legitimately take up to 45s
server-side. Cache-bumped api.js.

payload/user/remote_access/pager-webui/www/index.html

@@ -262,7 +262,7 @@
 
 <script src="js/config.js"></script>
 <script src="js/icons.js?v=20260818-7"></script>
-<script src="js/api.js?v=20260817-4"></script>
+<script src="js/api.js?v=20260819-2"></script>
 <script src="js/chart.js?v=20260819-1"></script>
 <script src="js/xterm.min.js"></script>
 <script src="js/xterm-addon-fit.min.js"></script>