feat: add pair programming implementation role and enhance orchestrator}
* Add new pair-implementer role for collaborative code generation with review cycles * Refactor orchestrator to support dynamic role composition and workflow management * Implement structured conversation patterns with validation and error handling * Update MCP module with improved message routing and context preservation * Add comprehensive CLI argument parsing and validation in architect.js * Update package.json dependencies and version information * Enhance README with detailed documentation of new pair programming workflow * Add changelog entries documenting all breaking changes and new features