解决minimap在图形长宽比和容器差异大时，缩略图跳转计算错误

[ttdys108]

比如图形长宽比1:10000，缩略图点击跳转错误

📝 Description

🖼️ Screenshot

Before	After
❌	✅

💡 Motivation and Context

🧩 Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Enhancement (changes that improvement of current feature or performance)
• Refactoring (changes that neither fixes a bug nor adds a feature)
• Test Case (changes that add missing tests or correct existing tests)
• Code style optimization (changes that do not affect the meaning of the code)
• Docs (changes that only update documentation)
• Chore (changes that don't modify src or test files)

🔍 Self Check before Merge

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[gemini-code-assist]

Code Review

This pull request refactors the scrollTo method in the MiniMap plugin to use pageX/pageY offsets relative to the target graph's container, avoiding coordinate inconsistencies caused by internal child elements. It also replaces the static this.ratio with the dynamic scale from this.targetGraph.transform.getScale() to fix coordinate deviations in non-scroller mode. The reviewer suggested adding defensive checks for Dom.offset to prevent potential runtime errors, handling potential division by zero or NaN for the scale factors, and updating the doAction method similarly to maintain consistency.

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[gemini-code-assist]

改进建议：
Dom.offset 在某些极端情况下（例如元素未挂载、处于测试环境或 DOM 结构异常时）可能会返回 null 或 undefined。如果直接访问其属性可能会导致运行时报错 TypeError: Cannot read properties of null。

建议进行防御性处理，为 containerOffset 提供一个默认值，例如 || { left: 0, top: 0 }，以增强代码的健壮性。

Suggested change

	const containerOffset = Dom.offset(this.targetGraph.container)
	const x = e.pageX - containerOffset.left
	const y = e.pageY - containerOffset.top
	const containerOffset = Dom.offset(this.targetGraph.container) || { left: 0, top: 0 }
	const x = e.pageX - containerOffset.left
	const y = e.pageY - containerOffset.top

[gemini-code-assist]

改进建议：

1. 除零/NaN 防御：在极端情况下（例如容器尺寸为 0、缩放比例异常或处于某些过渡动画中），targetScale.sx 或 targetScale.sy 可能会为 0 或 NaN。直接作为除数会导致计算结果为 Infinity 或 NaN，从而使 centerPoint 计算失效。建议对它们进行防御性处理，若为 0 或无效值，则回退到 this.ratio 或 1。
2. doAction 中的一致性问题：虽然本次修改解决了 scrollTo（点击跳转）中的缩放比不一致问题，但在 doAction 方法（处理拖拽平移，约第 274-280 行）中，依然在使用 this.ratio 进行坐标转换。在非 scroller 模式下，这同样会导致拖拽视口时出现偏差（拖拽速度与鼠标不贴合）。建议在后续重构或同一 PR 中，将 doAction 中的 this.ratio 也替换为 targetScale.sx 和 targetScale.sy，以保持逻辑的一致性。

const targetScale = this.targetGraph.transform.getScale()
const sx = targetScale.sx || this.ratio || 1
const sy = targetScale.sy || this.ratio || 1

const cx = (x - ts.tx) / sx
const cy = (y - ts.ty) / sy