Create a migration guide for updating between SDK versions

As the Reclaim Protocol SDK evolves, a comprehensive migration guide would be invaluable for developers updating their implementations.

Tasks:

1. Create a new markdown file named 'migration-guide.mdx'
2. In this file, include:
   • A table of contents listing all major versions
   • For each version update (e.g., v1.x to v2.x), provide:
     • A summary of major changes and new features
     • A detailed list of breaking changes
     • Step-by-step instructions for updating implementations
     • Code snippets showing before and after examples for major changes
   • A section on deprecated features and their planned removal dates
   • Guidelines for testing after migration
   • Troubleshooting tips for common issues encountered during migration
3. Add a section on best practices for keeping implementations up-to-date
4. Include links to release notes for each version
5. Provide guidance on how to report issues or seek help during migration

This guide will help developers smoothly transition between different versions of the Reclaim Protocol SDK, ensuring they can take advantage of new features and improvements while minimizing disruption to their applications.

Contributors: Please note that by submitting a pull request, you are agreeing to accept and sign the Contributor License Agreement (CLA) found at https://github.com/reclaimprotocol/.github/blob/main/CLA.md

Create migration-guide.mdx and first review the SDK's version history and release notes to identify the major version transitions, breaking changes, deprecated features, and relevant links. The work is complete when the guide covers every requested migration section, includes before-and-after examples and testing guidance, and explains how to get help or report issues.