refactor: sync managers and section box actions

Wire section box scale/reverse/reset to clipping APIs and sync demo artifacts.

src/managers/section-box-dialog-manager.ts

@@ -57,14 +57,21 @@ export class SectionBoxDialogManager extends BaseDialogManager {
                 }
             },
             onReverseToggle: (isReversed) => {
-                // 底层暂不支持反向功能
-                console.log('[SectionBoxDialogManager] 反向切换（底层暂不支持）：', isReversed);
+                console.log('[SectionBoxDialogManager] 反向切换：', isReversed);
+                // 底层 reverse() 为“切换一次”，这里不使用 isReversed 作为入参，只要用户点击就触发。
+                this.registry.engine3d?.reverseSection();
             },
             onFitToModel: () => {
-                console.log('[SectionBoxDialogManager] Fit to model not supported in new API');
+                // 对接底层 scaleBox()：缩放剖切盒到场景整体包围盒
+                this.registry.engine3d?.scaleSectionBox();
             },
             onReset: () => {
-                console.log('[SectionBoxDialogManager] Reset not supported in new API');
+                // 重置定义：关闭剖切再打开剖切盒。
+                // UI 侧会自行将滑块强制恢复到 0-100，并将隐藏/反向按钮恢复为关闭状态。
+                this.registry.engine3d?.deactivateSection();
+                this.registry.engine3d?.activeSection('box');
+                // 确保剖切可见（避免上一次处于隐藏状态导致“看起来没重置”）
+                this.registry.engine3d?.recoverSection();
             },
             onRangeChange: (range) => {
                 this.registry.engine3d?.setSectionBoxRange(range);