feat(func_metadata): expose skip_names argument

[NextFire]

Expose func_metadata's skip_names argument in the @tool decorator and move the if param.name in skip_names: check to the top.

Motivation and Context

It allows users to ignore specific parameters, such as optional ones and especially those starting with an underscore.

My use case was to programmatically wrap a generated SDK for Spotify (from openapi-generator-cli) into an MCP server. However, the client methods included optional arguments that started with an underscore, which led to InvalidSignature exceptions.

How Has This Been Tested?

https://github.com/NextFire/spotify-mcp-server/tree/with-pr-fix

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

[mcp-shadow]

Thank you for your contribution. We're rejecting this PR because bypassing the underscore parameter validation would circumvent an intentional design decision in the SDK and is not backwards compatible.

Instead, we recommend creating wrapper functions that have clean parameter names and delegate to your Spotify SDK.

If you believe there's a broader need for this functionality beyond your specific use case, please open a discussion with additional examples and use cases for community feedback.