style: dark theme site

[chenshuai2144]

🤔 This is a ...

• New feature
• Bug fix
• Site / document update
• Component style update
• TypeScript definition update
• Refactoring
• Code style optimization
• Test Case
• Branch merge
• Other (about what?)

🔗 Related issue link

no

💡 Background and solution

📝 Changelog

Language	Changelog
🇺🇸 English	support dark style
🇨🇳 Chinese	support dark style

☑️ Self Check before Merge

• 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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View rendered components/form/demo/advanced-search.md
View rendered docs/react/introduce.en-US.md
View rendered docs/react/introduce.zh-CN.md

[netlify]

Deploy preview for ant-design ready!

Built with commit 5a90c56

https://deploy-preview-18855--ant-design.netlify.com

[codecov]

Codecov Report

Merging #18855 into master will decrease coverage by 0.45%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #18855      +/-   ##
==========================================
- Coverage   97.38%   96.92%   -0.46%     
==========================================
  Files         280      281       +1     
  Lines        7526     7554      +28     
  Branches     2109     2105       -4     
==========================================
- Hits         7329     7322       -7     
- Misses        196      230      +34     
- Partials        1        2       +1

Impacted Files	Coverage Δ
components/_util/openAnimation.tsx	75% <0%> (-21.43%)	⬇️
components/transfer/renderListBody.tsx	90.62% <0%> (-9.38%)	⬇️
components/transfer/list.tsx	94.33% <0%> (-5.67%)	⬇️
components/date-picker/WeekPicker.tsx	94.8% <0%> (-5.2%)	⬇️
components/upload/Upload.tsx	95.45% <0%> (-3.79%)	⬇️
components/upload/UploadList.tsx	96.55% <0%> (-3.45%)	⬇️
components/transfer/index.tsx	95.48% <0%> (-3.23%)	⬇️
components/upload/utils.tsx	98.66% <0%> (-1.34%)	⬇️
components/date-picker/createPicker.tsx	98.91% <0%> (-1.09%)	⬇️
components/date-picker/RangePicker.tsx	95.06% <0%> (-0.62%)	⬇️
... and 9 more

---

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[buildsize]

File name	Previous Size	New Size	Change
package-lock.json	848.05 KB	853.26 KB	5.21 KB (1%)

[afc163]

建议放到 4.0 里

[afc163]

switch?

[afc163]

• 页脚的切换先改成开发环境可见，生产环境不放出来。
• 可以把 Enhance Theme Config Pane in Footer #12651 也搞掉？
• ci 挂了。