Feature: Quick prompt suggestions below chat input

[lbedner]

Overview

Add always-visible quick prompt suggestions below the chat input field, allowing users to select common prompts without typing commands.

User Experience

When input is empty, display selectable prompt chips:

You: _____________________

  [Explain code]  [Debug error]  [Write tests]  [Summarize]
  [Code review]   [Refactor]     [Add docs]     [More...]

Interaction:

• Arrow keys or number keys to select
• Enter to insert selected prompt into input
• Start typing to hide suggestions and use regular input
• Suggestions reappear when input is cleared

Implementation Approach

Using prompt_toolkit layout features:

1. Create a floating panel or bottom section showing prompt chips
2. Conditionally display when input buffer is empty
3. Add key bindings for navigation (arrows, numbers)
4. Insert selected prompt text into input buffer

Prompt Categories (example)

• Code: Explain, Debug, Refactor, Review, Write tests, Add docs
• Analysis: Summarize, Compare, Find issues, Suggest improvements
• Creative: Brainstorm, Generate ideas, Write copy

Configuration

• Prompts could be loaded from a config file (YAML/JSON)
• User-customizable prompt library
• Conditional prompts based on context (e.g., RAG-specific prompts when RAG is enabled)

Files to Modify

• app/cli/ai.py - Modify PromptSession layout
• app/cli/chat_completer.py - May need prompt navigation logic
• New: app/cli/quick_prompts.py - Prompt definitions and UI component

Reference

• prompt_toolkit layouts: https://python-prompt-toolkit.readthedocs.io/en/master/pages/advanced_topics/rendering_flow.html
• Current chat implementation: app/cli/ai.py lines 1005-1320