curl --request POST \
  --url https://api.liveavatar.com/v1/sessions/start \
  --header 'Authorization: Bearer <token>'

{
  "code": 100,
  "data": {
    "session_id": "<string>",
    "livekit_url": "<string>",
    "livekit_client_token": "<string>",
    "livekit_agent_token": "<string>",
    "max_session_duration": 123,
    "ws_url": "<string>"
  },
  "message": "<string>"
}