List Documents

curl --request GET \
  --url https://api.example.com/agents/{agent_id}/documents \
  --header 'Authorization: Bearer <token>'

{
  "agent_id": "<string>",
  "documents": [
    {
      "document_id": "<string>",
      "filename": "<string>",
      "content_type": "<string>",
      "checksum": "<string>",
      "created_at": "<string>",
      "size": 123
    }
  ],
  "total": 123
}