curl --request POST \
  --url https://api.prompt-wall.com/v1/chat \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "prompt": "<string>",
  "messages": [
    {
      "role": "system",
      "content": "<string>"
    }
  ],
  "model": "gpt-4o-mini",
  "provider": "openai",
  "temperature": 0.2
}
'

{
  "ok": true,
  "answer": "<string>",
  "confidence": "<string>",
  "governance_action": "<string>",
  "verified_source_used": true,
  "policy": "<string>",
  "latency_ms": 123,
  "tokens": {
    "prompt": 123,
    "completion": 123,
    "total": 123
  },
  "matches": [
    "<string>"
  ],
  "request_id": "<string>"
}