feat: support dimension hover state for MarkPoint targetSymbol

[xuefei1313]

[中文版模板 / Chinese template]

🤔 This is a ...

• New feature
• Bug fix
• TypeScript definition update
• Bundle size optimization
• Performance optimization
• Enhancement feature
• Refactoring
• Update dependency
• Code style optimization
• Test Case
• Branch merge
• Release
• Site / documentation update
• Demo update
• Workflow
• Other (about what?)

🔗 Related issue link

N/A

🔗 Related PR link

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🐞 Bugserver case id

N/A

💡 Background and solution

Previously, targetSymbol.state could define a dimension_hover style, but MarkPoint did not synchronize the state with the chart's dimensionHover event. Setting visible: false is unsuitable for this use case because it clears the pick bounds and causes hover flicker.

For Cartesian MarkPoint, when targetSymbol.state.dimension_hover or dimension_hover_reverse is configured, the component now compares the resolved marker x value with the active dimension and updates only the matching targetSymbol's VRender state on dimension enter/leave. Using opacity: 0.001 keeps the pick bounds intact.

targetSymbol: {
  visible: true,
  state: {
    dimension_hover: { opacity: 0.001 }
  }
}

A Browser demo and regression test cover the behavior.

📝 Changelog

Language	Changelog
🇺🇸 English	MarkPoint targetSymbol now supports the dimension_hover and dimension_hover_reverse states for Cartesian dimension hover.
🇨🇳 Chinese	Cartesian MarkPoint 的 targetSymbol 现支持 dimension_hover 和 dimension_hover_reverse 状态，可随维度悬停自动切换。

☑️ Self-Check before Merge

• Doc is not needed
• Demo is provided
• TypeScript definition is updated
• Changelog is provided

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🚀 Summary

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🔍 Walkthrough

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