docs: add the rmcp-openapi and rmcp-actix-web related projects

[JMLX42]

Update the README with more related projects

Motivation and Context

Community building.

How Has This Been Tested?

N/A

Breaking Changes

N/A

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)
• Documentation update

Checklist

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

[4t145]

I think we should make them more clear, some project are extension of rmcp while some are just using rmcp. So maybe we should split them into two parts?

[JMLX42]

I think we should make them more clear, some project are extension of rmcp while some are just using rmcp. So maybe we should split them into two parts?

Maybe have a subsection for the libs that extend rmcp and and another subsection for the projects built on rmcp?

[4t145]

@JMLX42 exactly!

[JMLX42]

@4t145 done!