Issue #, if available:

Description of changes:

Testing

With tool enabled - q settings chat.enableThinking true

with tool disabled - q settings chat.enableThinking false

Trusted tools can be run without confirmation

* Default settings

> use think tool

I don't have a "think tool" available in my current toolset. The tools I can use include:

• fs_write: For creating and editing files
• use_aws: For making AWS CLI API calls
• execute_bash: For executing bash commands
• fs_read: For reading files and directories
• report_issue: For reporting issues with the chat

Is there something specific you'd like me to help you with using these available tools? I can help with file operations, AWS CLI commands, bash execution, or other tasks related to the Amazon Q CLI project you're working on.

Add Think Tool with Configurable Enablement

Description

This PR introduces a new "Think" tool that enhances Amazon Q's reasoning capabilities during chat interactions. The Think tool provides a dedicated space for the model to process information, navigate
complex decision trees, and improve response quality in multi-step scenarios.

Key Features

• Added a new think.rs module implementing the Think tool functionality
• Integrated the tool into the existing tools framework
• Made the feature configurable via settings (q settings enable_thinking [true|false])
• Added conditional tool registration based on the feature flag
• Implemented blue-colored visual feedback when the model shares its reasoning process

Implementation Details

• The Think tool allows the model to explicitly reason through complex problems during response generation
• When enabled, the tool displays the model's thought process in blue text
• The feature is enabled by default but can be disabled via settings
• Empty thoughts are accepted but ignored to maintain robustness
• The tool is completely excluded from the available tools list when disabled

Technical Changes

• Added new file: crates/q_cli/src/cli/chat/tools/think.rs (86 lines)
• Modified tool registration in load_tools() to conditionally include the Think tool
• Updated tool index JSON to include the Think tool definition
• Added tool handling in the Tool enum and related functions
• Implemented validation, invocation, and description methods for the tool

Usage

Users can control this feature with:
q settings enable_thinking true # Enable the thinking feature (default)
q settings enable_thinking false # Disable the thinking feature

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.