docs: 文档装修

[visiky]

PR includes

• documents, demos

Description

官网文档梳理：文档结构

• 一级横向导航，同 G2：教程（manual） + API（API）+ 图表示例
• 图表示例下的二级导航
  • 将长尾图表收纳到「更多图表」分类下，让目录结构更简洁直观
  • 适当进行图表分类，如：桑基图和和弦图 归类在「关系图」下

Screenshot

Before	After
❌	✅

[github-actions]

😭 Deploy PR Preview a78e70b failed. Build logs

_{🤖 By surge-preview}

[coveralls]

Pull Request Test Coverage Report for Build 431583421

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-0.03%) to 96.746%

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Files with Coverage Reduction	New Missed Lines	%
src/utils/transform/word-cloud.ts	1	97.75%

Totals
Change from base Build 430215330:	-0.03%
Covered Lines:	4369
Relevant Lines:	4407

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💛 - Coveralls

[visiky]

改个文档，测试覆盖也可以下载？