Function send_json_request 

pub async fn send_json_request<T>(
    method: Method,
    url: impl Into<String>,
    api_key: impl AsRef<str>,
    body: &T,
    config: Arc<HttpClientConfig>,
) -> ZaiResult<Response>
where
    T: Serialize + ?Sized,

Send a JSON request through the shared transport pipeline.

Emits a single always-on trace line carrying the raw sent JSON body (masked via mask_sensitive_info), so the wire payload is observable with RUST_LOG=trace. Per the library-silent logging policy, the success path produces no higher-level output; only retries are surfaced (warn!).

enable_logging on HttpClientConfig is retained for API stability but no longer adds output — the trace line already covers that need.