[Feat]: 边的控制点（顶点）能手动调整

### Describe the feature / 功能描述

我希望能手动控制边的控制点，类似于x6的调整顶点 https://x6.antv.antgroup.com/examples/edge/tool/#vertices
谢谢

### Are you willing to contribute? / 是否愿意参与贡献？

❌ No / 否

Start by reviewing G6's edge interaction architecture and the linked X6 vertices example to understand the expected behavior. Done should mean users can manually adjust an edge's control points or vertices through direct interaction, with the behavior covered by the relevant tests.

Written by the indexing model from the issue text.