Create a message in thread

curl --request POST \
  --url https://api.anyapi.ai/v1/threads/{thread_id}/messages \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "role": "user",
  "content": "<string>"
}'

{
  "id": "<string>",
  "object": "message",
  "thread_id": "<string>",
  "role": "<string>",
  "content": [
    {}
  ],
  "created_at": 123
}