[v5] 新功能需求，select-element交互，批量拖拽选中的polyline edge时，可以更新controlPoints

### 问题描述

问题描述：现在的方式，批量拖拽polyline时，controlpoints是固定的，体验很不优雅
诉求：希望动态更新controlPoints，让edge的移动看起来像是整体移动

### 重现链接

无

### 重现步骤

很简单，就不重现了

### 预期行为

希望动态更新controlPoints，让edge的移动看起来像是整体移动

### 平台

- 操作系统: [macOS, Windows, Linux, React Native ...]
- 网页浏览器: [Google Chrome, Safari, Firefox]
- G6 版本: [4.5.1 ... ]

### 屏幕截图或视频（可选）

_No response_

### 补充说明（可选）

_No response_

Start by locating the select-element interaction for batch-dragging selected polyline edges and the code that manages their controlPoints. Establish a reproducible example, then define completion as dynamically updating controlPoints so each edge appears to move as a whole during the drag.

Written by the indexing model from the issue text.