perf: faster map boot — zoom-gate heavy layers, static basemap, defer HUD, lazy HLS

World view no longer fetches cameras/NWS/WFIGS. Default Blue Marble so init
does not wait on GIBS times. News/summary/events load with their views.
hls.min.js loads only on the first HLS camera popup.

app/static/index.html

@@ -1026,10 +1026,22 @@
 <script src="/static/vendor/leaflet/leaflet.js"></script>
 <script src="/static/vendor/leaflet/leaflet.markercluster.js"></script>
 <script src="/static/vendor/leaflet/leaflet.heat.js"></script>
-<script src="/static/vendor/hls/hls.min.js"></script>
 <script>
 const API = '';
 
+function loadHls() {
+    if (window.Hls) return Promise.resolve();
+    if (window._hlsLoading) return window._hlsLoading;
+    window._hlsLoading = new Promise((res, rej) => {
+        const s = document.createElement('script');
+        s.src = '/static/vendor/hls/hls.min.js';
+        s.onload = res;
+        s.onerror = rej;
+        document.head.appendChild(s);
+    });
+    return window._hlsLoading;
+}
+
 /* ═══════════════ BOOT SPLASH ═══════════════ */
 (function () {
     const boot = document.getElementById('boot');
@@ -1136,7 +1148,8 @@ function showView(name) {
         }
     }
     if (name === 'news') loadNews(false);
-    if (name === 'settings') renderSysInfo();
+    if (name === 'events') { loadSummary(); loadEvents(); }
+    if (name === 'settings') { loadSummary(); renderSysInfo(); }
     window.scrollTo(0, 0);
 }
 
@@ -1651,7 +1664,10 @@ async function initMap() {
         const sel = document.getElementById('map-layer');
         sel.innerHTML = mapLayers.map(l =>
             `<option value="${l.id}">${l.title}</option>`).join('');
-        const preferred = mapLayers.find(l => l.has_time) || mapLayers[0];
+        const preferred =
+            mapLayers.find(l => l.id === 'BlueMarble_ShadedRelief_Bathymetry')
+            || mapLayers.find(l => !l.has_time)
+            || mapLayers[0];
         if (preferred) sel.value = preferred.id;
         map = L.map('map', {
             center: [25, 10], zoom: 2,
@@ -1676,6 +1692,7 @@ async function initMap() {
                 img.alt = 'camera preview';
                 v.replaceWith(img);
             };
+            const startHls = () => {
                 if (window.Hls && Hls.isSupported()) {
                     activeHls = new Hls({ enableWorker: true, lowLatencyMode: true });
                     activeHls.loadSource(v.dataset.hls);
@@ -1690,6 +1707,9 @@ async function initMap() {
                 } else {
                     fallback();
                 }
+            };
+            if (window.Hls) startHls();
+            else loadHls().then(startHls).catch(fallback);
         });
         map.on('popupclose', () => {
             if (activeHls) { try { activeHls.destroy(); } catch (_) {} activeHls = null; }
@@ -1719,7 +1739,8 @@ async function initMap() {
                 refreshLiveOverlays();
             }, 300);
         });
-        await mapLayerChanged();
+        // Static Blue Marble has no time-domain fetch — don't block overlays on GIBS.
+        mapLayerChanged();
         // Overlays default ON (checkboxes in the layer panel + saved settings)
         applyMapSettings(readMapPrefs(), false);
         firesOn = document.getElementById('lp-fires-on').checked;
@@ -2036,6 +2057,13 @@ function camThumb(c) {
 }
 async function loadCams() {
     if (!map) return;
+    if (tooZoomedOut()) {
+        camsGroup = dropLayer(camsGroup);
+        markZoom('lp-cams-count');
+        hudCamsCount = null;
+        syncHud();
+        return;
+    }
     const req = ++camReq;
     try {
         const r = await fetch(`${API}/api/cameras?bbox=${currentBBox()}&limit=5000`);
@@ -2175,6 +2203,14 @@ function dropLayer(ref) {
     if (ref && map && map.hasLayer(ref)) map.removeLayer(ref);
     return null;
 }
+/* Polygon/camera layers hitch at world scale. Same idea as aircraft's zoom<=3
+   skip: do not fetch or render these until the user is zoomed in. */
+const HEAVY_MIN_ZOOM = 4;
+function tooZoomedOut() { return !map || map.getZoom() <= HEAVY_MIN_ZOOM; }
+function markZoom(id) {
+    const el = document.getElementById(id);
+    if (el) el.textContent = 'zoom';
+}
 function intersectsConus() {
     if (!map) return false;
     const b = map.getBounds();
@@ -2338,6 +2374,11 @@ async function toggleWxAlerts() {
 }
 async function loadWxAlerts() {
     if (!map) return;
+    if (tooZoomedOut()) {
+        wxAlertsGroup = dropLayer(wxAlertsGroup);
+        markZoom('lp-alerts-count');
+        return;
+    }
     const req = ++overlayReq.alerts;
     try {
         const r = await fetch(`${API}/api/weather-alerts?bbox=${currentBBox()}`);
@@ -2369,6 +2410,11 @@ async function togglePerimeters() {
 }
 async function loadPerimeters() {
     if (!map) return;
+    if (tooZoomedOut()) {
+        perimGroup = dropLayer(perimGroup);
+        markZoom('lp-perim-count');
+        return;
+    }
     const req = ++overlayReq.perim;
     try {
         const r = await fetch(`${API}/api/fire-perimeters?bbox=${currentBBox()}`);
@@ -2402,6 +2448,11 @@ async function toggleIncidents() {
 }
 async function loadIncidents() {
     if (!map) return;
+    if (tooZoomedOut()) {
+        incidentsGroup = dropLayer(incidentsGroup);
+        markZoom('lp-incidents-count');
+        return;
+    }
     const req = ++overlayReq.incidents;
     try {
         const r = await fetch(`${API}/api/fire-incidents?bbox=${currentBBox()}`);
@@ -2511,9 +2562,9 @@ async function loadStorms() {
 initNav();
 initSettings();
 initMarketTicker();
-loadSummary(); loadEvents(); loadNews(true); checkHealth();
-setInterval(() => { loadSummary(); loadEvents(); checkHealth(); }, 30000);
+checkHealth();
 initMap();
+setInterval(checkHealth, 30000);
 </script>
 </body>
 </html>