Replace Three.js globe with Cesium

Migrate the globe view to a Cesium viewer with Esri satellite
imagery and terrain, dropping the custom blue-marble texture and
dot-bead rendering. Add vite-plugin-cesium and a container element
for the viewer.

Also rework the binder leather and suede materials with dedicated
normal maps, and refine timeline labels and page hole sizing.

src/styles.css

@@ -26,6 +26,15 @@ html, body {
 
 #app { position: fixed; inset: 0; }
 #scene { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }
+#cesium-container {
+  position: absolute; inset: 0; width: 100%; height: 100%;
+  display: none; background: #14100d;
+}
+#cesium-container .cesium-viewer,
+#cesium-container .cesium-widget,
+#cesium-container canvas { width: 100%; height: 100%; }
+/* 隐藏左下角全部归属信息（Cesium ion logo + 影像文字） */
+#cesium-container .cesium-widget-credits { display: none !important; }
 
 /* 气氛遮罩 */
 .vignette {