完善建筑外观切换与宿主页面适配

src/components/map/ThreeMap.vue

@@ -5142,9 +5142,30 @@ const handleFloorChange = async (floorId: string) => {
 }
 
 const showOverview = async () => {
-  // 建筑外观不再作为手动切换入口；只在初始加载与缩放自动切换时展示。
   if (activeView.value === 'overview') {
     resetCamera()
+    return
+  }
+
+  const previousLoadToken = modelLoadVersion
+  try {
+    isLoading.value = true
+    loadError.value = false
+    clearMapSelection(false)
+    clearRoutePreview()
+    await loadOverview()
+  } catch (error) {
+    if (!isStaleModelLoadError(error)) {
+      console.error('建筑外观模型加载失败:', error)
+      loadError.value = true
+      setFriendlyModelLoadError()
+    }
+    throw error
+  } finally {
+    const requestWasSuperseded = modelLoadVersion > previousLoadToken + 1
+    if (!requestWasSuperseded) {
+      isLoading.value = false
+    }
   }
 }