chore: move to ESLint Flat Config

[eiinu]

这个 PR 做了什么? (简要描述所做更改)

1、迁移到 ESLint Flat Config 配置
2、移除 eslint-plugin-prettier，引入 stylistic

这个 PR 是什么类型? (至少选择一个)

• feat: 新特性提交
• fix: bug 修复
• docs: 文档改进
• style: 组件样式/交互改进
• type: 类型定义更新
• perf: 性能、包体积优化
• refactor: 代码重构、代码风格优化
• test: 测试用例
• chore(deps): 依赖升级
• chore(demo): 演示代码改进
• chore(locale): 国际化改进
• chore: 其他改动（是关于什么的改动？）

这个 PR 涉及以下平台:

• NutUI H5 @nutui/nutui
• NutUI Taro @nutui/nutui-taro

这个 PR 是否已自测:

• 自测 Vite 脚手架使用 测试仓库
• 自测 Taro 脚手架使用小程序 & Taro-H5 测试仓库

[codecov]

Codecov Report

Attention: Patch coverage is 77.31481% with 98 lines in your changes are missing coverage. Please review.

Project coverage is 84.00%. Comparing base (35984c0) to head (3cdd0ea).

Files	Patch %	Lines
src/packages/__VUE/calendaritem/index.vue	53.33%	17 Missing and 4 partials ⚠️
src/packages/utils/date.ts	0.00%	11 Missing ⚠️
src/packages/__VUE/countup/index.vue	79.06%	9 Missing ⚠️
src/packages/__VUE/notify/index.ts	0.00%	4 Missing ⚠️
src/packages/__VUE/toast/index.ts	33.33%	4 Missing ⚠️
src/packages/__VUE/video/index.vue	77.77%	4 Missing ⚠️
src/packages/utils/create/mountComponent.ts	0.00%	4 Missing ⚠️
src/packages/utils/util.ts	0.00%	4 Missing ⚠️
src/packages/__VUE/audio/index.vue	72.72%	3 Missing ⚠️
src/packages/__VUE/uploader/uploader.ts	25.00%	3 Missing ⚠️
... and 22 more

Additional details and impacted files

@@            Coverage Diff             @@
##               v4    #3003      +/-   ##
==========================================
+ Coverage   83.95%   84.00%   +0.05%     
==========================================
  Files         210      210              
  Lines       23202    23296      +94     
  Branches     2545     2542       -3     
==========================================
+ Hits        19479    19570      +91     
- Misses       3705     3708       +3     
  Partials       18       18              

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