Add chatbot-outliner.tsx and ct-prompt-input

[bfollington]

Summary by cubic

Adds a new chatbot-outliner pattern that pairs an LLM chat with an interactive outliner. Users can chat, switch models, and let the assistant add outline nodes via a tool.

• New Features
  • New recipe with two tabs: Chat and Tools (renders ct-outliner bound to the outline).
  • Tool: appendOutlinerNode appends a node to outline.root.children (JSON schema + handler).
  • Model selector populated from /api/ai/llm/models; default model set to anthropic:claude-sonnet-4-0.
  • Clear Chat and Cancel controls for message flow.
  • Strong typing for Outliner and Page, plus helpers for sending and clearing messages.