feat(UST-1087): create `nuxt` and `next` packages

[jagoral]

🔗 Linked issue

❓ Type of change

• [ ] 📖 Documentation (updates to the documentation, readme or JSDoc annotations)
• [ ] 🐞 Bug fix (a non-breaking change that fixes an issue)
• [ ] 👌 Enhancement (improving an existing functionality like performance)
• [x] ✨ New feature (a non-breaking change that adds functionality)
• [ ] 🧹 Chore (updates to the build process or auxiliary tools and libraries)
• [x] ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

📚 Description

• Created a @vue-storefront/nuxt package for Vue Storefront 2
• Created a @vue-storefront/nextjs package (support for Pages and App Router)
• Added a Nuxt Module which facilitates the setup of SDK for Nuxt Storefronts
• Added unit and shared e2e tests
• Added a base README for the module, presenting how to set it up
• nuxt package requires Node.js v18, therefore as a workaround:
  • storefront package have been placed within packages/storefront/packages dir
  • packages/storefront has been excluded from the Yarn workspaces
  • packages/storefront creates a nested workspace
  • a custom continuous-delivery-storefront.yml workflow has been created (runs tests on Node18)
  • release of storefront packages wouldn't be possible with changeset, till we will migrate the whole repo to Node18, we will have to release them manually
• for Next.js @vue-storefront/next/client entry is exported, where a "use client" directive is used, so the code can be used in App Router

How to test it locally?

1. cd packages/storefront
2. yarn

Then for Next

1. cd packages/next
2. yarn build
3. yarn dev:middleware in one terminal
4. yarn dev:pages-router or yarn dev:app-router in second terminal

or Nuxt

1. cd packages/nuxt
2. yarn build
3. yarn dev:middleware in one terminal
4. yarn dev:pages-router or yarn dev in second terminal

📝 Checklist

• [x] I have linked an issue or discussion.
• [ ] I have updated the documentation accordingly.
• [x] JSDocs included

[skirianov]

Added docs for getting started with Next, Nuxt, and Framework Agnostic

@jagoral @filrak please let me know wdyt

[skirianov]

fixed CR @jagoral

@filrak can you lift your change requested?