Feature Request: Persistent chat history with directory isolation

[jmmoser]

Feature Description

Add persistent chat history that survives CLI restarts and is isolated by working directory.

Problem Statement

Currently, when users restart the Amazon Q CLI, all previous chat history is lost. Users cannot use up-arrow navigation to access previous commands from earlier sessions, which reduces productivity and user experience.

Proposed Solution

Implement persistent chat history with the following features:

Core Functionality

• Persistent storage: Chat history survives CLI restarts using SQLite database
• Directory isolation: History for /project/a is separate from /project/b
• Up-arrow navigation: Works seamlessly with persistent history
• Automatic cleanup: Maintain max number of entries per directory to prevent unlimited growth

User Experience

• No configuration required - works out of the box
• Transparent integration with existing readline functionality
• Per-directory isolation matches user mental model

Use Cases

• Developers working on multiple projects can maintain separate command history
• Long-running development sessions benefit from persistent history across restarts
• Power users with frequent CLI usage get improved productivity