SAML SSO enforcement breaking OAuth client credentials flow for Terraform provider

We have recently enforced SAML Single Sign-On (SSO) for all human users in our Genesys Cloud organization via the Identity Provider integration. This is working correctly for agents and supervisors logging into the web UI. However, this change has inadvertently broken our automated infrastructure pipeline which relies on the CX-as-Code Terraform provider.

The provider uses the genesyscloud data source to fetch an OAuth token using the client credentials grant type. Previously, this worked without issue. Now, the plan phase fails immediately with a 401 Unauthorized error when attempting to initialize the client. The error message returned is quite generic:

Error: Error authenticating with Genesys Cloud: 401 Unauthorized

We assumed that SAML settings only affect interactive browser logins and not machine-to-machine authentication. The Terraform configuration for the provider is standard:

provider "genesyscloud" {
 client_id = var.genesys_client_id
 client_secret = var.genesys_client_secret
 base_url = "https://api.eu.genesys.cloud"
}

We verified that the OAuth client in the Genesys Cloud admin portal still has the admin scope and is active. The client itself has not been disabled. Is there a specific setting in the SAML configuration or the OAuth client definition that needs to be adjusted to allow non-interactive access when SSO is mandatory for the tenant?

We tried testing the token endpoint directly via cURL to rule out a Terraform provider bug. The request looks like this:

curl -X POST https://api.eu.genesys.cloud/oauth/token \
 -H "Content-Type: application/x-www-form-urlencoded" \
 -d "grant_type=client_credentials&client_id=OUR_CLIENT_ID&client_secret=OUR_SECRET"

This also returns a 401. It seems the platform is rejecting the client credentials grant entirely now that SAML is enforced. We need to maintain SSO for humans but require programmatic access for our IaC pipelines. What is the correct configuration to restore OAuth client credentials flow in this scenario?