[Feature]: 为Line PolyLine 也添加getPath方法

[wumail]

背景&目的

I tried to use logicflow to incorporate some brilliant featrues with custom line, but found that it was not easy to get the path of the line, I hope you can help me, thank you very much. Love from china❤
something like:

[DymoneLewis]

Can you join us to do this? we need you
plllllllllleeeeeeeeeeeeease sir
Love from china too🤡