Streaming & debugging

async def process_question_stream(question: str):
    """Stream node execution events for debugging visualization"""
    initial_state = AgentState(
        question=question,
        sql_query="",
        query_result="",
        final_answer="",
        error="",
        iteration=0,
        needs_graph=False,
        graph_type="",
        graph_json="",
        is_in_scope=True,
        guardrails_reason="",
        sql_reason="",
        graph_reason=""
    )

    current_state = initial_state.copy()

    try:
        # Stream events from the graph
        async for event in text2sql_graph.astream_events(
            initial_state,
            config={"recursion_limit": 50},
            version="v1"
        ):
            event_type = event.get("event")

            if event_type == "on_chain_start":
                node_name = event.get("name", "")
                yield {"type": "node_start", "node": node_name}

            elif event_type == "on_chain_end":
                node_name = event.get("name", "")
                output = event.get("data", {}).get("output", {})
                current_state.update(output)
                yield {"type": "node_end", "node": node_name, "output": output}

        yield {"type": "final", "result": current_state}

    except Exception as e:
        yield {"type": "error", "error": str(e)}