feat: 聚合方式支持count

[Alexzjt]

👀 PR includes

✨ Feature

• New feature

🎨 Enhance

• Code style optimization
• Refactoring
• Change the UI
• Improve the performance
• Type optimization

🐛 Bugfix

• Solve the issue and close 🙏希望aggregation多一个计数 COUNT 的 方法 #3138

🔧 Chore

• Test case
• Docs / demos update
• CI / workflow
• Release version
• Other ()

📝 Description

🖼️ Screenshot

Before	After
❌	✅

🔗 Related issue link

🔍 Self-Check before the merge

• Add or update relevant docs.
• [] Add or update relevant demos.
• Add or update test case.
• Add or update relevant TypeScript definitions.

[github-actions]

你好 @Alexzjt，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, @Alexzjt, 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.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.88%. Comparing base (ecdc9c8) to head (39bc4f3).
Report is 654 commits behind head on next.

Additional details and impacted files

@@            Coverage Diff             @@
##             next    #3143      +/-   ##
==========================================
+ Coverage   75.77%   79.88%   +4.11%     
==========================================
  Files         257      217      -40     
  Lines       11994    11894     -100     
  Branches     2464     2661     +197     
==========================================
+ Hits         9088     9502     +414     
+ Misses       1398      790     -608     
- Partials     1508     1602      +94     

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[github-actions]

Size Change: +47 B (+0.01%)

Total Size: 625 kB

Filename	Size	Change
./packages/s2-core/dist/s2-extends.min.js	156 kB	+21 B (+0.01%)
./packages/s2-core/dist/s2.min.js	260 kB	+26 B (+0.01%)

ℹ️ View Unchanged

Filename	Size
./packages/s2-core/dist/s2.min.css	581 B
./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	1.74 kB
./packages/s2-react/dist/s2-react.min.js	38.3 kB
./packages/s2-vue/dist/s2-vue.min.css	2.05 kB
./packages/s2-vue/dist/s2-vue.min.js	38.3 kB

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