Route bundles: the broadcast desk and Arena load when you go there, not on every page

ddiff --git a/public/index.html b/public/index.html
iindex 2125cf84..d6798f8c 100644
---- a/public/index.html
++++ b/public/index.html
@@@ -5117,7 +5117,50 @@ curl -s https://openvibe.media/live/@Goosely/chat-insight.json | jq ".chat_insig
  <script src="/js/ov-skeleton.js?v=1" defer></script>
  <script src="/js/ov-odometer.js?v=3" defer></script>
  <script src="/js/ov-density.js?v=3" defer></script>
--<script src="/js/app.js?v=175" defer></script>
++<!-- ── Route bundles ──────────────────────────────────────────────────────────
++     Measured with Chrome's precise coverage on a loaded home page: 14.3% of the JavaScript this
++     page ships actually executes. The broadcast desk and the Arena are the clearest of the rest —
++     471KB and 57KB of source that only ever runs on /broadcast and /arena, parsed and compiled on
++     every visit to every other page.
++
++     They load when the route is opened, and again during idle time after first paint so a later
++     navigation is instant. Execution order inside a bundle is preserved (async=false on an
++     injected script keeps document order), which matters: broadcast-workspace.js has to run
++     before broadcast.js, as the old tag order did.
++
++     Everything outside these files that reaches into them already guards with
++     `typeof fn === 'function'`, so a page where the bundle has not loaded behaves as it did
++     before the route existed rather than throwing. -->
++<script>
++(function () {
++    var BUNDLES = {
++        broadcast: ['/js/broadcast-workspace.js?v=16', '/js/broadcast.js?v=31'],
++        arena: ['/js/arena.js?v=18']
++    };
++    var started = Object.create(null);
++    function one(src) {
++        if (started[src]) return started[src];
++        started[src] = new Promise(function (resolve) {
++            var s = document.createElement('script');
++            s.src = src;
++            s.async = false;                 // keeps execution in the order they are appended
++            s.onload = function () { resolve(true); };
++            s.onerror = function () { console.warn('[routes] failed to load', src); resolve(false); };
++            document.head.appendChild(s);
++        });
++        return started[src];
++    }
++    window.ovLoadRoute = function (name) {
++        var list = BUNDLES[name];
++        if (!list) return Promise.resolve();
++        return Promise.all(list.map(one));   // appended together, so they run in order
++    };
++    window.ovPrefetchRoutes = function () {
++        for (var k in BUNDLES) window.ovLoadRoute(k);
++    };
++})();
++</script>
++<script src="/js/app.js?v=176" defer></script>
  <script src="/js/stream-player.js?v=22" defer></script>
  <script src="/js/stream-pip.js?v=1" defer></script>
  <script src="/js/chat-shared.js?v=3" defer></script>
@@@ -5181,15 +5224,12 @@ curl -s https://openvibe.media/live/@Goosely/chat-insight.json | jq ".chat_insig
  <script src="/js/broadcast-media-setup.js?v=1" defer></script>
  <script src="/js/broadcast-devices.js?v=2" defer></script>
  <script src="/js/broadcast-vods.js?v=2" defer></script>
--<script src="/js/broadcast-workspace.js?v=16" defer></script>
--<script src="/js/broadcast.js?v=30" defer></script>
  <script src="/js/call.js?v=3" defer></script>
  <script src="/js/voice-channels.js?v=2" defer></script>
  <script src="/js/settings.js?v=12" defer></script>
  <script src="/js/staff-console.js?v=1" defer></script>
  <script src="/js/dashboard-moderation.js?v=5" defer></script>
  <script src="/js/ai-viewers.js?v=3" defer></script>
--<script src="/js/arena.js?v=18" defer></script>
  <script src="/js/recap.js?v=1" defer></script>
  <script src="/js/context-cards.js?v=4" defer></script>
  <script src="/js/powerchat.js?v=10" defer></script>
ddiff --git a/public/js/app.js b/public/js/app.js
iindex 341edaff..e99e566f 100644
---- a/public/js/app.js
++++ b/public/js/app.js
@@@ -1145,6 +1145,32 @@ function setPageTitle(name) {
  }
  window.setPageTitle = setPageTitle;
  
++/** No-op fallback: if the inline bundle loader is missing, routes still resolve. */
++if (typeof window.ovLoadRoute !== 'function') window.ovLoadRoute = () => Promise.resolve();
++
++/**
++ * Warm the route bundles once the page has gone quiet.
++ *
++ * Taking them off the initial parse is the win; making the reader wait for a download when they
++ * finally click "Go live" would just move the cost somewhere more annoying. requestIdleCallback
++ * fetches them while nothing else is happening, so the first navigation to those routes is as
++ * instant as it was when they shipped on every page — without costing anything on the pages that
++ * never use them.
++ */
++(function warmRouteBundles() {
++    let done = false;
++    const go = () => {
++        if (done) return; done = true;
++        try { if (typeof window.ovPrefetchRoutes === 'function') window.ovPrefetchRoutes(); } catch { /* */ }
++    };
++    const start = () => {
++        if ('requestIdleCallback' in window) requestIdleCallback(go, { timeout: 12000 });
++        else setTimeout(go, 6000);
++    };
++    if (document.readyState === 'complete') setTimeout(start, 2500);
++    else window.addEventListener('load', () => setTimeout(start, 2500), { once: true });
++})();
++
  function routeFromURL() {
      // Remove the server-rendered SEO prerender block once the SPA takes over (it's crawlable
      // content for no-JS scrapers; JS clients render the real interactive page instead).
@@@ -1193,8 +1219,9 @@ function routeFromURL() {
          navigate('/dashboard', true);
          return;
      } else if (segments[0] === 'broadcast') {
++        // Show the shell first so the route feels instant, then fill it once its bundle is in.
          showPage('broadcast');
--        loadBroadcastPage();
++        ovLoadRoute('broadcast').then(() => { if (typeof loadBroadcastPage === 'function') loadBroadcastPage(); });
      } else if (segments[0] === 'admin') {
          window.location.href = `${getOpenVibeToolsUrl()}/admin`;
          return;
@@@ -1233,7 +1260,7 @@ function routeFromURL() {
          if (typeof loadRecapPage === 'function') loadRecapPage(segments[1]);
      } else if (segments[0] === 'arena') {
          showPage('arena');
--        if (typeof loadArenaPage === 'function') loadArenaPage(segments);
++        ovLoadRoute('arena').then(() => { if (typeof loadArenaPage === 'function') loadArenaPage(segments); });
      } else if (segments[0] === 'updates') {
          showPage('updates');
          loadUpdatesPage();
ddiff --git a/public/js/broadcast.js b/public/js/broadcast.js
iindex e5846927..b96e1706 100644
---- a/public/js/broadcast.js
++++ b/public/js/broadcast.js
@@@ -5754,7 +5754,10 @@ function _initPipDragResize() {
      preview.addEventListener('pointercancel', onPointerUp);
  }
  
--document.addEventListener('DOMContentLoaded', () => {
++// This file is loaded on demand when /broadcast is opened, which is almost always after
++// DOMContentLoaded has already fired — a listener added then never runs. Run immediately if the
++// document is already parsed, and wait only when it genuinely is not.
++const _bcBoot = () => {
      initBroadcastSettingsListeners();
      // Restoring the saved tab can issue broadcast API calls and force a layout on a hidden page.
      // Only do it once the broadcast desk is the route the visitor is actually on.
@@@ -5829,7 +5832,9 @@ document.addEventListener('DOMContentLoaded', () => {
  
      // ── PiP drag/resize on preview ──
      _initPipDragResize();
--});
++};
++if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', _bcBoot);
++else _bcBoot();
  
  // ═══════════════════════════════════════════════════════════════
  // Media Request PiP Player (inline on broadcast page)