Add missing imports in README.md example

[TheFloatingString]

I added missing imports for the quickstart example in the README.md file

Motivation and Context

Saves developers potential import errors when trying the quickstart

How Has This Been Tested?

Had some difficulty running MPC as TypeScript on my local machine, so I'd recommend someone else test the proposed README.md instructions before merging.

Breaking Changes

Only changes the README.md contents

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• [ X] Documentation update

Checklist

• [ X] I have read the MCP Documentation
• [ X] My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• [ X] I have added or updated documentation as needed

Additional context

[jspahrsummers]

Thank you!