feat(clerk-js,nextjs,clerk-react,types): Add support for new init flow

[colinclerk]

Type of change

• [ ] 🐛 Bug fix
• [x] 🌟 New feature
• [ ] 🔨 Breaking change
• [ ] 📖 Refactoring / dependency upgrade / documentation
• [ ] other:

Packages affected

• [x] @clerk/clerk-js
• [x] @clerk/clerk-react
• [x] @clerk/nextjs
• [ ] @clerk/remix
• [x] @clerk/types
• [ ] @clerk/themes
• [ ] @clerk/clerk-expo
• [ ] @clerk/backend-core
• [ ] @clerk/clerk-sdk-node
• [ ] @clerk/edge
• [ ] build/tooling/chore

Description

This PR adds a new initialization flow to support authentication state syncing via URL decoration instead of third party cookies. This provides better DX in Safari, Firefox, Chrome Incognito, and iframe-based solutions like repl.it and stackblitz.

It is currently a work-in-progress. There are many

• [ ] npm test runs as expected.
• [ ] npm run build runs as expected.