curl --request POST \
  --url https://api.replicas.dev/v1/replica/{id}/messages \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "message": "<string>",
  "coding_agent": "claude",
  "chat_id": "<string>",
  "model": "<string>",
  "images": [
    {
      "type": "<string>",
      "source": {
        "type": "<string>",
        "media_type": "image/png",
        "data": "<string>"
      }
    }
  ],
  "plan_mode": true
}
'

{
  "status": "sent",
  "message_id": "<string>",
  "position": 123,
  "chat_id": "<string>"
}