feat(site): support system theme-mode auto switch

[HaixingOoO]

🤔 这个 PR 的性质是？

• 日常 bug 修复
• 新特性提交
• 文档改进
• 演示代码改进
• 组件样式/交互改进
• CI/CD 改进
• 重构
• 代码风格优化
• 测试用例
• 分支合并
• 其他

🔗 相关 Issue

💡 需求背景和解决方案

官网支持自动切换系统主题

📝 更新日志

• feat(site): support system theme-mode auto switch

• 本条 PR 不需要纳入 Changelog

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• 文档已补充或无须补充
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[tencent-adm]

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[pkg-pr-new]

Open in StackBlitz

npm i https://pkg.pr.new/Tencent/tdesign/@tdesign/site-components@742

npm i https://pkg.pr.new/Tencent/tdesign/tdesign-theme-generator@742

commit: 6e2d1a1

[tdesign-bot]

TDesign Component Site Preview CI Open

Sites (8)

Component	Preview
tdesign-site
tdesign-vue
tdesign-react
tdesign-vue-next
@tdesign-vue-next/chat
tdesign-mobile-vue
tdesign-mobile-react
tdesign-miniprogram