Function build_compute 

pub async fn build_compute(
    cfg: Option<&ComputeConfig>,
    storage: Arc<dyn Storage>,
    data_dir: &Path,
    node_id: u64,
    strict: bool,
    daemon: Option<Arc<DaemonRuntime>>,
    worker_exe: Option<&Path>,
) -> (BackendRegistry, Node)

Build this node’s compute [BackendRegistry] + scheduler [Node] inventory from the optional [compute] config. Backends are capability-detected: a reachable Docker daemon ⇒ docker; Linux ⇒ the native container backend; Linux + /dev/kvm ⇒ the in-process vmm-embedded microVM backend (strongest isolation). Absent config ⇒ an empty registry + a node advertising nothing, so the reconcile loop stays a no-op.