Update a single graph node

{
  "id": "string",
  "organization_id": "string",
  "test_mode": true,
  "agent_id": "string",
  "name": "string",
  "description": "string",
  "version": -2147483648,
  "status": "draft",
  "graph": {
    "entry_node": "string",
    "nodes": {
      "property1": {
        "type": "question",
        "key": "string",
        "text": "string",
        "objective": "string",
        "required": true,
        "probing": {
          "enabled": true,
          "max_follow_ups": 0,
          "techniques": [
            "string"
          ],
          "completion_hint": "string"
        }
      },
      "property2": {
        "type": "question",
        "key": "string",
        "text": "string",
        "objective": "string",
        "required": true,
        "probing": {
          "enabled": true,
          "max_follow_ups": 0,
          "techniques": [
            "string"
          ],
          "completion_hint": "string"
        }
      }
    },
    "edges": [
      {
        "from": "string",
        "to": "string",
        "condition": {
          "type": "structured",
          "field": "string",
          "operator": "eq",
          "value": null
        },
        "priority": 0
      }
    ]
  },
  "settings": {
    "estimated_duration_m": 1,
    "max_duration_m": 1,
    "intro_message": "string",
    "outro_message": "string",
    "language": "string",
    "consent": true
  },
  "pipeline": {
    "transcript": true,
    "responses": true,
    "analysis": true
  },
  "metadata": {
    "property1": null,
    "property2": null
  },
  "published_at": "string",
  "created_at": "string",
  "updated_at": "string",
  "object": "blueprint",
  "agent": {
    "id": "string",
    "organization_id": "string",
    "test_mode": true,
    "name": "string",
    "description": "string",
    "persona": {
      "system_prompt": "string",
      "tone": "conversational",
      "language": "string"
    },
    "voice": {
      "provider": "string",
      "voice_id": "string",
      "speed": 0.5
    },
    "techniques": [
      "funnel"
    ],
    "probing_depth": "light",
    "boundaries": {
      "max_follow_ups_per_question": 0,
      "off_topic_handling": "gentle_redirect",
      "sensitive_topics": [
        "string"
      ]
    },
    "model_config": {
      "generation": {
        "provider": "anthropic",
        "model": "string"
      },
      "assessment": {
        "provider": "anthropic",
        "model": "string"
      }
    },
    "metadata": {
      "property1": null,
      "property2": null
    },
    "created_at": "string",
    "updated_at": "string",
    "object": "agent"
  }
}