Ingest messages from external platforms

curl --request POST \
  --url http://localhost:3000/api/messaging/ingest-external \
  --header 'Content-Type: application/json' \
  --data '{
  "agentId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "roomId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "userId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "text": "<string>",
  "sourceId": "<string>",
  "sourceType": "discord",
  "metadata": {}
}'

{
  "success": true
}