feat: Tool name format checks (SEP-986)

[nbarbettini]

Motivation and Context

Closes #238

How Has This Been Tested?

Against the latest TS SDK:

node dist/index.js server --url http://localhost:3100/mcp --scenario tools-list
Running client scenario 'tools-list' against server: http://localhost:3100/mcp
Checks:
2026-04-21T13:47:42.403Z [tools-list       ] SUCCESS Server lists available tools with valid structure
2026-04-21T13:47:42.403Z [tools-name-format] SUCCESS Tool names are 1-64 characters and match ^[A-Za-z0-9_./-]+$

Test Results:
Passed: 2/2, 0 failed, 0 warnings

Breaking Changes

None

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

[pkg-pr-new]

Open in StackBlitz

npx https://pkg.pr.new/@modelcontextprotocol/conformance@240

commit: 05e10ec

[pcarleton]

@nbarbettini this should ~trivially pass on all SDK's since the scenario definition defines the tool names. I suppose it will check that we haven't busted our own rules in scenario writing, but is this targeted more towards the mcp-debugger case testing against a live server?