docs: Translate s2-site documentation from Chinese to English

[google-labs-jules]

This PR translates a significant portion of the markdown documentation in the s2-site/common and s2-site/docs directories from Chinese to English. The English files have been updated to match the more comprehensive Chinese versions, and new English files have been created where they were missing.

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PR created automatically by Jules for task 8241080793691637326 started by @Alexzjt

[google-labs-jules]

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[github-actions]

你好 @google-labs-jules[bot]，非常感谢你的贡献.
为了让代码更健壮, 请根据 贡献指南 补充相应单元测试 (文档改动或其他特殊场景除外), 如果有 API 改动, 请修改 相应的文档.
同时请检查 lint 和 test 相关 CI 是否通过, 如果失败, 请点击 [Details] 按钮查看, 并根据日志修复.

Hello, @google-labs-jules[bot], Thanks for your contribution. In order to make the code more robust, please add the corresponding unit tests, and update the docs if there are API changes.
At the same time, please check whether the CI related to lint and test passes. If the CI fails, please click [Details] button to check and repair according to the log.

[github-actions]

你好, @google-labs-jules[bot] CI 执行失败, 请点击 [Details] 按钮查看, 并根据日志修复

Hello, @google-labs-jules[bot] CI run failed, please click the [Details] button for detailed log information and fix it.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 79.62%. Comparing base (ecdc9c8) to head (9768317).
⚠️ Report is 734 commits behind head on next.

Additional details and impacted files

@@            Coverage Diff             @@
##             next    #3263      +/-   ##
==========================================
+ Coverage   75.77%   79.62%   +3.85%     
==========================================
  Files         257      217      -40     
  Lines       11994    12006      +12     
  Branches     2464     2692     +228     
==========================================
+ Hits         9088     9560     +472     
+ Misses       1398      817     -581     
- Partials     1508     1629     +121     

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[github-actions]

Size Change: -2 B (0%)

Total Size: 628 kB

Filename	Size	Change
./packages/s2-core/dist/s2.min.css	581 B	-2 B (-0.34%)

ℹ️ View Unchanged

Filename	Size
./packages/s2-core/dist/s2-extends.min.js	158 kB
./packages/s2-core/dist/s2.min.js	263 kB
./packages/s2-react-components/dist/s2-react-components.min.css	2.55 kB
./packages/s2-react-components/dist/s2-react-components.min.js	124 kB
./packages/s2-react/dist/s2-react.min.css	1.3 kB
./packages/s2-react/dist/s2-react.min.js	38.5 kB
./packages/s2-vue/dist/s2-vue.min.css	1.59 kB
./packages/s2-vue/dist/s2-vue.min.js	38.3 kB

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