feat: upgrade iflow-engine-base to v1.0.5, add pause/resume rendering API

- Update iflow-engine-base from 1.0.1 to 1.0.5
- Change default engine version from v1 to v2
- Add pauseRendering() and resumeRendering() methods
- Add switch model feature in demos
- Update model URLs in demos
- Add new documentation files

src/managers/engine-manager.ts

@@ -105,6 +105,24 @@ export class EngineManager extends BaseManager {
         this.engineInstance.CameraGoHome();
     }
 
+    /** 暂停渲染 */
+    public pauseRendering(): void {
+        if (!this.engineInstance) {
+            console.warn('[EngineManager] 3D Engine not initialized.');
+            return;
+        }
+        this.engineInstance.pauseRendering();
+    }
+
+    /** 恢复渲染 */
+    public resumeRendering(): void {
+        if (!this.engineInstance) {
+            console.warn('[EngineManager] 3D Engine not initialized.');
+            return;
+        }
+        this.engineInstance.resumeRendering();
+    }
+
     /**
      * 激活测量模式
      * @param mode 测量模式