feat: intro `@zendeskgarden/codemods` + add `v8-v9` migration transforms

[ze-flo]

Description

🚀 Introducing...

   __ _  __ _ _ __ __| | ___ _ __     ___ ___   __| | ___ _ __ ___   ___   __| |___
  / _` |/ _` | '__/ _` |/ _ \ '_ \   / __/ _ \ / _` |/ _ \ '_ ` _ \ / _ \ / _` / __|
 | (_| | (_| | | | (_| |  __/ | | | | (_| (_) | (_| |  __/ | | | | | (_) | (_| \__ \
  \__, |\__,_|_|  \__,_|\___|_| |_|  \___\___/ \__,_|\___|_| |_| |_|\___/ \__,_|___/
  |___/

The @zendeskgarden/codemods package offers a variety of codemods designed to automate code transformations in Garden-based projects.

Detail

• Introduces the new package @zendeskgarden/codemods
• Adds v8-to-v9 codemods. Each codemod is aligned with the v9 migration guide
• Tests transforms in various scenarios
• Adds detailed docs
• Links available codemod to v9 migration guide when available

Checklist

• [ ] :ok_hand: design updates will be Garden Designer approved (add the designer as a reviewer)
• [ ] :globe_with_meridians: demo is up-to-date (npm start)
• [ ] :arrow_left: renders as expected with reversed (RTL) direction
• [ ] :black_circle: renders as expected in dark mode
• [ ] :metal: renders as expected with Bedrock CSS (?bedrock)
• [x] :guardsman: includes new unit tests. Maintain existing coverage (always >= 96%)
• [ ] :wheelchair: tested for WCAG 2.1 AA accessibility compliance
• [ ] :memo: tested in Chrome, Firefox, Safari, and Edge

[coveralls]

coverage: 95.08% (-0.8%) from 95.923% when pulling 98288d5f00bad7dd829189a28f2cf34998da64f7 on ze-flo/garden-codemods into ddb2d0cf5b7620cb922d6c185f46f1ce66540ed9 on main.