Fix for #56 - missing method attribute from client RPC message

[tomakehurst]

Motivation and Context

Per #56 Cursor (and apparently some other MCP clients) don't send the method attribute in the params map in their notification messages, whereas this server requires it to be present, throwing an NPE when it's not and thus preventing successful initialisation.

How Has This Been Tested?

Tested manually with the latest version of Cursor - 0.46.8

Breaking Changes

No

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

Additional context

Draft at present, as automating a test will require modifying the client code (or pulling in an alternative client) to behave like Cursor and others.

[tomakehurst]

This probably isn't the cleanest way to implement this fix, but better options will probably require some more invasive surgery on the codebase.