feat: 添加假 API 接口以获取用户信息，并更新 Cesium 示例代码

src/pages/cesium/cesium-helper/demo_02_Track.ts

@@ -1,5 +1,5 @@
 import * as Cesium from 'cesium';
-import { type Viewer } from 'cesium';
+import { Cartesian3, type Viewer } from 'cesium';
 import { eciToEcf, gstime, propagate, twoline2satrec } from 'satellite.js';
 
 /**
@@ -45,6 +45,8 @@ export async function demo_02_Track(viewer: Viewer) {
       outlineWidth: 2,
       pixelSize: 10,
     },
+    // viewFrom: new Cartesian3(0, -1.5e7, 2.5e7),
+    // https://www.google.com/search?q=cesium%C2%A0viewFrom%C2%A0+trackedEntity
   });
 
   // 计算并绘制卫星轨迹