fix: 修复 center.js 文件的 center 方法高程计算错误的BUG

src/modules/math/center.js

 
 export default function center(positions) {
   if (positions && Array.isArray(positions)) {
+    let heightMax = 0 // 位置最高的点的高度
+    positions.forEach(({ alt }) => (heightMax = Math.max(heightMax, alt)))
+
     let boundingSphere = Cesium.BoundingSphere.fromPoints(
       Transform.transformWGS84ArrayToCartesianArray(positions)
     )
-    return Transform.transformCartesianToWGS84(boundingSphere.center)
+    const position = Transform.transformCartesianToWGS84(boundingSphere.center)
+    position.alt = heightMax
+    return position
   }
 
   return new Position()