feat(globe): port to CeliumJS

scripts/copy-cesium.js

@@ -0,0 +1,24 @@
+// Copies Cesium's runtime assets into static/ so they are served at /cesium/.
+// Cesium fetches Workers/Assets/Widgets/ThirdParty at runtime by URL (see
+// CESIUM_BASE_URL in src/app.html); they cannot be bundled by Vite. static/ is
+// copied verbatim in both dev and build, so this needs no Vite plugin.
+// Regenerated on every `npm install` via the prepare script.
+import { cpSync, existsSync, mkdirSync, rmSync } from 'node:fs';
+import { dirname, join } from 'node:path';
+import { fileURLToPath } from 'node:url';
+
+const root = join(dirname(fileURLToPath(import.meta.url)), '..');
+const src = join(root, 'node_modules', 'cesium', 'Build', 'Cesium');
+const dest = join(root, 'static', 'cesium');
+
+if (!existsSync(src)) {
+	console.error(`[copy-cesium] missing ${src} — is cesium installed?`);
+	process.exit(1);
+}
+
+rmSync(dest, { recursive: true, force: true });
+mkdirSync(dest, { recursive: true });
+for (const dir of ['Assets', 'ThirdParty', 'Widgets', 'Workers']) {
+	cpSync(join(src, dir), join(dest, dir), { recursive: true });
+}
+console.log('[copy-cesium] assets copied to static/cesium/');