默认行为drag-combo没有触发shouldEnd事件

### Describe the bug

开启drag-combo，通过拖动combo内的空白区域调整combo位置，鼠标松开后没有触发shouldEnd

### Your Example Website or App

https://g6.antv.vision/zh/examples/interaction/combo/#rect

### Steps to Reproduce the Bug or Issue

1. 官网demo可复现，测试代码如下：
```js
{
type: 'drag-combo',
enableDelegate: false,
shouldEnd(e) {
console.log('end', e);
return false;
},
},
```
2. 通过拖动combo内的空白区域调整combo位置，鼠标松开后没有触发shouldEnd

### Expected behavior

combo拖动到画布上时也能正常触发shouldEnd

### Screenshots or Videos

_No response_

### Platform

- OS: macOS
- Browser: Chrome
- Version: 124.0.6367.92

### Additional context

_No response_

Start with the drag-combo interaction in the linked combo example and reproduce the issue using enableDelegate: false and the provided shouldEnd callback. Compare dragging the combo’s blank area with other drag paths, then verify that releasing on the canvas consistently invokes shouldEnd.

Written by the indexing model from the issue text.