Function fetch_hardware 

pub async fn fetch_hardware(
    target: &TargetEndpoint,
    timeout: Duration,
) -> Hardware

2026-09-26: GET /hardware: the serving box’s hardware fingerprint.

Fetched from the endpoint rather than probed locally because a benchmark number belongs to the box that did the inference, which is not necessarily the box running the benchmark CLI. Any failure (bad target, connect, timeout, no JSON, wrong shape) returns crate::hardware::Hardware::unknown, so a server without the endpoint does not make a run unrecordable.