def update_metrics(detected_items):
    """
    Update metrics from detection results.
    Args:
        detected_items: List of detection dictionaries
    Returns:
        dict: Metrics summary including items
    """
    if not detected_items:
        return {"items": [], "count": 0, "avg_confidence": 0.0}

    count = len(detected_items)
    avg_confidence = sum(item["confidence"] for item in detected_items if "confidence" in item) / count if count > 0 else 0.0

    return {
        "items": detected_items,
        "count": count,
        "avg_confidence": avg_confidence
    }