Add complete label management functionality to GitHub MCP server

[clafollett]

Overview

This feature request is to add comprehensive label management capabilities to the GitHub MCP server, allowing AI agents to interact with GitHub labels through the Model Context Protocol.

Features to Add

• Create new labels in a repository
• Retrieve details about existing labels
• List all labels in a repository
• Update existing label properties (name, color, description)
• Delete labels from a repository
• Add labels to issues
• Remove labels from issues
• List all labels on an issue

Benefits

• Enables AI agents to fully manage GitHub labels programmatically
• Provides a complete interface to GitHub's label APIs to give better context to new labels