refactor(map): 优化倾斜摄影初始化中的viewer引用

- 将多次调用getViewer()替换为函数内单一变量viewer缓存
- 统一使用viewer参数调用createObliquePhotography函数
- 提升代码可读性及性能，避免重复获取viewer实例

src/pages/Container/Map/js/useInitMap.js

@@ -23,31 +23,32 @@ export default function useInitMap(options) {
 
   // 倾斜摄影
   const initObliquePhotography = () => {
-    getViewer().scene.globe.depthTestAgainstTerrain = true;
+    const viewer = getViewer();
+    viewer.scene.globe.depthTestAgainstTerrain = true;
     Cesium.ExperimentalFeatures.enableModelExperimental = true;
     createObliquePhotography(
       "http://192.168.192.215:8021/ware/upload/%E6%9B%B9%E5%A6%83%E7%94%B8%E6%B8%AF%E4%B8%9C/%E6%9B%B9%E5%A6%83%E7%94%B8%E6%B8%AF%E4%B8%9C/merge_tile.json",
-      getViewer(),
+      viewer,
     );
     createObliquePhotography(
       "http://192.168.192.215:8021/ware/upload/%E6%9B%B9%E5%A6%83%E7%94%B8%E6%B8%AF%E8%A5%BF/%E6%9B%B9%E5%A6%83%E7%94%B8%E6%B8%AF%E8%A5%BF/merge_tile.json",
-      getViewer(),
+      viewer,
     );
     createObliquePhotography(
       "http://192.168.192.215:8021/ware/upload/qhdxys/merge_tile.json",
-      getViewer(),
+      viewer,
     );
     createObliquePhotography(
       "http://192.168.192.215:8021/ware/upload/qhdgysh/merge_tile.json",
-      getViewer(),
+      viewer,
     );
     createObliquePhotography(
       "http://192.168.192.215:8021/ware/upload/%E6%B2%A7%E5%B7%9E%E6%B8%AF%E8%A5%BF/%E6%B2%A7%E5%B7%9E%E6%B8%AF%E8%A5%BF/merge_tile.json",
-      getViewer(),
+      viewer,
     );
     createObliquePhotography(
       "http://192.168.192.215:8021/ware/upload/%E6%B2%A7%E5%B7%9E%E6%B8%AF%E4%B8%9C/%E6%B2%A7%E5%B7%9E%E6%B8%AF%E4%B8%9C/merge_tile.json",
-      getViewer(),
+      viewer,
     );
   };