Feat/point sampling

[skie1997]

[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

close #460

🔗 Related PR link

VisActor/VGrammar#225

🐞 Bugserver case id

65395f4b159a621b655d9ff1
65395ee3159a621b655d9ff0

💡 Background and solution

新增功能：

• 折线图、柱状图 数据采样
• 折线图point mark 防重叠

实现思路：
1、数据采样：

• 依赖vGrammar的data transform，type: 'sampling'，支持'lttb' | 'min' | 'max' | 'sum' | 'avergae' 。采样算法参考：https://github.com/apache/echarts/blob/master/src/processor/dataSample.ts
• 在line、bar series 中自定义compiler逻辑, 通过this._data.getProduct().transform()为数据注入transform

2、图元防重叠：依赖vGrammar的mark transform，type：'markoverlap'

• 在line series 中自定义compiler逻辑, 通过this._symbolMark.getProduct().transform()为数据注入transform

📝 Changelog

Language	Changelog
🇺🇸 English
🇨🇳 Chinese

☑️ Self-Check before Merge

⚠️ Please check all items below before requesting a reviewing. ⚠️

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

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🚀 Summary

copilot:summary

🔍 Walkthrough

copilot:walkthrough