message: Fix JetStream response matching order
  Serde matches untagged enums in the order they are listed, so error must
  come first to take priority in cases where error is sent along with
  additional data.
diff: @@ -257,6 +257,11 @@ impl JetStreamOptions {
  #[derive(Debug, Serialize, Deserialize)]
  #[serde(untagged)]
  enum ApiResponse<T> {
  + // Note:
  + // Serde will try to match the data against each variant in order and the first one that
  + // deserializes successfully is the one returned.
  + //
  + // Therefore the error case must come first, otherwise it can be ignored.
  Err { r#type: String, error: Error },
  Ok(T),
  }
  