Add think tool for complex reasoning

[bhouston]

Description

This PR adds a new think tool to the default set of tools in MyCoder. The think tool allows the agent to explicitly think through complex problems without taking any external actions. It serves as a way to document the agent's reasoning process and can improve problem-solving abilities.

Implementation Details

• Added a new think tool in packages/agent/src/tools/think/
• Added the tool to the default set of tools in getTools.ts
• Implemented tests for the new tool
• All tests are passing

Motivation

This implementation is based on the request in issue #351, which references research from Anthropic showing how a simple "think" tool can improve Claude's problem-solving skills.

Related Issues

Resolves #351

Example Usage

await toolAgent.execute({
  name: 'think',
  parameters: {
    thought: 'I need to consider all possible solutions before deciding on an approach.'
  }
});

The tool will log the thought process and return the thought without performing any external actions.