[Feat]: 使用二次贝塞尔曲线时，两个节点之间有两条线，有办法调整两线在节点交互处的间距吗

### Describe the feature / 功能描述

使用二次贝塞尔曲线时，两个节点之间有两条线，有办法调整两线在节点交互处的间距吗

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

❌ No / 否

Start by reproducing the reported case from the attached image with two nodes connected by two quadratic Bézier curves. Locate the graph edge-rendering entry point responsible for quadratic curves and determine how spacing at the node intersections could be configured. Done means the two lines have adjustable separation at their node endpoints; the issue names no files or tests to run.

Written by the indexing model from the issue text.