refactor: drag canvas can be triggered on elements

[Aarebecca]

• Drag Canvas 交互能够在元素上触发

过去，DragCanvas 只能在指针位于画布空白处时才能触发，无法在位于元素上方时触发
现在只需要将 enable 置为 true，即可在任意位置激活拖动画布交互

{
  type: 'drag-canvas',
  enable: true
}

⚠️ 警告：该配置项下默认情况下会和 DragElement 交互有冲突，建议通过更多事件参数进行条件区分

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• Drag Canvas can be triggered on elements

In the past, DragCanvas could only be triggered when the pointer was in a blank area of the canvas, not when it was above an element
Now just need to set enable to true to activate drag-canvas behavior anywhere

⚠️ Warning: This options item conflicts with DragElement behavior by default. It is recommended to use more event parameters to distinguish conditions