Better MCP module interface rails support

[patvice]

🚀 Rails Integration, Module Interface improvements and Transport Layer Refactoring

This PR adds comprehensive Rails support to the RubyLLM MCP library and refactors the transport layer for better extensibility.

✨ What's New

Rails Integration

• Rails Railtie: Automatic MCP client lifecycle management

  • Starts all configured MCP clients when Rails initializes (configurable)
  • Gracefully shuts down clients when Rails application exits
  • Automatic generator registration

• Rails Generator: Easy setup with rails generate ruby_llm:mcp:install

  • Creates config/initializers/ruby_llm_mcp.rb with comprehensive configuration
  • Generates config/mcps.yml with sample MCP server configuration
  • Includes setup instructions and usage examples

MCP module interface

• Added some support methods to MCP to make it easy to work with multiple MCPs.
• Added a global tools method to more easily work with tools across multiple MCPs.

Transport Layer Improvements

• New Transport Factory Pattern: Centralized transport type registration and management
• Better Process Management: Improved handling of transport instances across process boundaries
• Enhanced Configuration: Support for YAML configuration files with ERB templating

Configuration Enhancements

• YAML Support: Use .yml files instead of JSON for more readable configuration
• Rails-Specific Options:
  • launch_control: :automatic or :manual MCP client management
  • config_path: Rails-aware configuration file paths
• Template Support: ERB processing in configuration files (e.g., <%= Rails.root %>)