Refactor toolAgent.ts into modular components

[bhouston]

Closes #63\n\n## Overview\nThis PR refactors the toolAgent.ts file into several smaller, focused modules to improve maintainability and testability:\n\n- config.ts: Extracted configuration-related code\n- messageUtils.ts: Extracted message handling utilities\n- toolExecutor.ts: Extracted tool execution logic\n- tokenTracking.ts: Enhanced the existing TokenTracker with more utilities\n- toolAgent/index.ts: Simplified main file that orchestrates the components\n- types.ts: Consolidated all type definitions\n\n## Benefits\n- Improved maintainability with smaller, focused files\n- Better testability through isolated components\n- Clearer responsibilities with each module having a single purpose\n- Easier onboarding for new developers\n- Simpler future extensions with a modular design\n\n## Implementation\n- Extracted types to a separate file\n- Extracted configuration\n- Moved utility functions to their respective files\n- Refactored the main toolAgent function to use the new modules\n- Added backward compatibility layer in the original toolAgent.ts\n- Added documentation in README.md\n\n## Testing\nAll existing tests pass, demonstrating backward compatibility.

[sentry-io]

Suspect Issues

This pull request was deployed and Sentry observed the following issues:

• ‼️ AI_InvalidToolArgumentsError: Invalid arguments for tool subAgent: Type validation failed: Value: {"description":"Update config test file to match new default config values","goal":"Update the /Users/benhouston/Coding/Business/mycoder/packages/cli/tests/settings/config.test.ts fi... toolAgent(index.ts) View Issue
• ‼️ AI_APICallError: The security token included in the request is invalid. toolAgent(index.ts) View Issue
• ‼️ AI_RetryError: Failed after 3 attempts. Last error: Too many tokens, please wait before trying again. toolAgent(index.ts) View Issue
• ‼️ Error: 400 The last message of deepseek-reasoner must be a user message, or an assistant message with prefix mode on (refer to https://api-docs.deepseek.com/guides/chat_prefix_completion). Object.doGenerate(config.ts) View Issue

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[github-actions]

🎉 This PR is included in version mycoder-agent-v1.0.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[github-actions]

🎉 This PR is included in version mycoder-v1.0.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀