Function fetch_trust_root 

pub async fn fetch_trust_root(
    registry_url: &str,
    client: &impl RegistryClient,
) -> Result<TrustRoot, TransparencyWorkflowError>

Fetch the trust root from a registry URL.

Issues a GET to {registry_url}/v1/trust-root, parses the JSON response, and converts it into a domain TrustRoot.

Args:

• registry_url — Base URL of the auths registry.
• client — Network client for HTTP communication.

Usage:

let trust_root = fetch_trust_root("https://registry.auths.dev", &http_client).await?;