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/scene/timeline.js

@@ -72,14 +72,12 @@ export class Timeline {
       outline.visible = false;
       card.add(outline);
 
-      // 活页上方：主题（常显，随选中上浮）
-      const name = makeTextSprite(entry.name, { fontSize: 30, color: '#e8d9b4' });
-      name.scale.multiplyScalar(0.22);
+      // 活页上方：主题（常显，随选中上浮，超宽居中换行）
+      const name = makeTextSprite(entry.name, { fontSize: 17, color: '#e8d9b4', scale: 0.13, maxWidth: 1.0 });
       name.position.set(x, NAME_Y, 0);
 
       // 轴下方：时间（常显，固定不动）
-      const time = makeTextSprite(entry.time, { fontSize: 22, color: '#c9a227' });
-      time.scale.multiplyScalar(0.18);
+      const time = makeTextSprite(entry.time, { fontSize: 13, color: '#c9a227', scale: 0.11 });
       time.position.set(x, -1.06, 0);
 
       this.group.add(card, name, time);