请问是否可以设置dagre布局的rank（层级）。 #2245

• I have searched the issues of this repository and believe that this is not a duplicate.

What problem does this feature solve?

比如简单来说，类似，git主分支复制一条副分支出来之后主分支不提交了，在副分支提交。那么整个记录只有一条线，但应该岔开显示。是否有类似机制设置rank

What does the proposed API look like?

可以主动设置rank分级

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