fix: resolve blank screen on return from external links

frontend/src/views/MapView.vue

@@ -143,10 +143,28 @@ async function fetchData() {
   updateActiveUnits();
 }
 
-function handleRefocus() {
+async function handleRefocus() {
+  // Refrescar datos en fondo
   fetchData();
+
+  await nextTick();
+
   if (map.value) {
-    google.maps.event.trigger(map.value, 'resize');
+    // El mapa sigue vivo — solo redimensionar y actualizar
+    try {
+      google.maps.event.trigger(map.value, 'resize');
+    } catch (_) { /* ignorar si google no disponible */ }
+    updateActiveUnits();
+  } else {
+    // El mapa fue destruido por el browser al suspender la pestaña — reinicializar
+    console.log('SIBU | Mapa perdido tras refocus, reinicializando...');
+    if (isLoaded.value) {
+      await initializeMap();
+    } else {
+      const unwatch = watch(isLoaded, async (loaded) => {
+        if (loaded) { await initializeMap(); unwatch(); }
+      });
+    }
   }
 }
 
@@ -154,7 +172,7 @@ function handleRefocus() {
 onMounted(async () => {
   analyticsService.logEvent({ event_name: 'screen_view', properties: { screen_name: 'Map' } })
   window.addEventListener('app-refocus', handleRefocus);
-  
+
   await fetchData();
 
   const queryRouteId = router.currentRoute.value.query.routeId as string;
@@ -179,7 +197,6 @@ onMounted(async () => {
   unitFetchInterval.value = setInterval(updateActiveUnits, 15000);
   startCarousel();
 
-  // 🛰️ RESIZE FIX: Trigger map resize when app becomes visible again
   document.addEventListener('visibilitychange', handleVisibilityChange);
 });
 
@@ -192,8 +209,9 @@ onUnmounted(() => {
 
 function handleVisibilityChange() {
   if (document.visibilityState === 'visible' && map.value) {
-    console.log('SIBU | App visible, redimensionando mapa...');
-    google.maps.event.trigger(map.value, 'resize');
+    try {
+      google.maps.event.trigger(map.value, 'resize');
+    } catch (_) { /* ignorar */ }
     updateActiveUnits();
   }
 }