Run the Navara paths without the Cesium SDK, and load it on demand for the features that still build on it

Every Cesium read that a Navara page made was surveyed with the strict acceptance (GEV_QA_CESIUM_TRAP=record). Math on those paths now uses src/geo: screen annotations, weather and wind center readings, cyclone picks, scene data pack polygons and images (new navaraGeometry.js), the awareness subject, the orbit offset of camera verbs, voice frame_overhead, the agent world packet and Directions colours and ground picks. The celestial ring's Sun and Moon come from a bit-identical port of Cesium's Simon1994 model, JulianDate and TEME rotation (src/geo/simon1994.js, julianDate.js, transforms.js); a Cesium globe still applies its ICRF rotation once loaded.

Traffic, Street Level, the Nepal event and locator and geo import build on Cesium's math or entity model on either globe; their enable (or the import) now loads the SDK first through src/app/loadCesium.js, synchronously when it is already there. A production page guards the global so a missed read is reported and starts the load. No module reads Cesium while it loads (scripts/check-cesium-load-time.mjs, run by npm test). Cesium.js is still loaded by index.html here.

src/layers/wind/edgeCases.test.mjs

@@ -7,22 +7,9 @@ import { inspectWindAtCenter } from './inspection.js';
 import { windReadingResult } from './presentation.js';
 import { sampleWind, windColor, windSpeed } from './model.js';
 import { windStats } from './index.js';
+import * as geo from '../../geo/index.js';
 
-const cesium = {
-  Cartesian2: class {
-    constructor(x, y) {
-      this.x = x;
-      this.y = y;
-    }
-  },
-  Ellipsoid: { WGS84: {} },
-  Cartographic: { fromCartesian: (p) => p },
-  Math: { toDegrees: (x) => (x * 180) / Math.PI },
-};
-const at = (lonDeg, latDeg) => ({
-  longitude: (lonDeg * Math.PI) / 180,
-  latitude: (latDeg * Math.PI) / 180,
-});
+const at = (lonDeg, latDeg) => geo.cartesian3.fromDegrees(lonDeg, latDeg);
 const grid = { nx: 4, ny: 3, lo1: 0, la1: 90, dx: 90, dy: 90 };
 const field = (u, v) => ({
   grid,
@@ -44,11 +31,10 @@ const viaViewer = (snapshot, point) =>
       camera: { pickEllipsoid: () => point },
       scene: { canvas: { clientWidth: 800, clientHeight: 600 } },
     },
-    cesium,
     options,
   );
 const viaPosition = (snapshot, point) =>
-  inspectWindAtCenter(snapshot, null, cesium, { ...options, position: point });
+  inspectWindAtCenter(snapshot, null, { ...options, position: point });
 const windLine = (reading) =>
   windReadingResult(reading).lines.find(({ id }) => id === 'wind').text;