Improve code organization, type safety, and add tests

[spacexbt]

This PR introduces several improvements to the codebase:

Code Organization & Type Safety

• Split GameAgent class into smaller, more focused components
• Extracted logger functionality into a separate service
• Added proper error boundary handling with custom error types
• Improved type safety throughout the codebase
• Added input validation for critical parameters

Performance & Resource Management

• Added cleanup method for proper resource management
• Improved state management in GameAgent
• Added validation for function configuration and arguments

Testing

• Added comprehensive unit tests for GameAgent
• Added comprehensive unit tests for GameFunction
• Added test coverage for error cases and edge scenarios

Changes

1. Created new files:

   • errors.ts: Custom error types for better error handling
   • logger.ts: Dedicated logging service
   • Added test files: agent.test.ts and function.test.ts

2. Enhanced existing files:

   • Improved agent.ts with better state management and error handling
   • Enhanced function.ts with improved validation and error handling
   • Updated type definitions for better type safety

Testing

All tests are passing and provide good coverage of the core functionality.