[bouillipx]

Add AskUserTool as a framework-built-in tool that is automatically registered for every agent, allowing the LLM to ask structured questions when it needs user clarification, decisions, or approval.

• AskUserTool: ITool implementation with structured question schema
• IUserInputHandler: callback protocol for host apps (CLI, web, etc.)
• CLIUserInputHandler: default stdin/stdout implementation
• Builder auto-registers ask_user; no manual add_tools() needed
• with_user_input_handler() on builder for custom handler injection

Summary

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Agent Rules Checklist (required)

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