func (c *OpenID4VPClient) OpenIdCredentialIssuerMetadata(ctx context.Context, oauthIssuerURI string) (*oauth.OpenIDCredentialIssuerMetadata, error) {
    iamClient := c.httpClient
    rsp, err := iamClient.OpenIdCredentialIssuerMetadata(ctx, oauthIssuerURI)
    if err != nil {
        return nil, fmt.Errorf("failed to retrieve Openid credential issuer metadata: %w", err)