How to Issue Refunds to Store Credit via Magento API?

I’m using Magento 2 Commerce (EE) on Adobe Commerce Cloud and want to issue refunds to a customer’s store credit balance programmatically via the REST API. While I know that store credit functionality is supported natively in Magento Commerce (e.g., refunds to store credit through the admin panel), I’m unable to find a single API endpoint to handle this use case.

Here’s what I’ve tried so far:

I attempted to use the POST /V1/creditmemo/refund API with the following payload:

{
“items”: [
{
“item_id”: “item”,
“qty”: 1
}
],
“is_online”: true,
“notify”: true,
“arguments”: {
“shipping_amount”: 0,
“adjustment_positive”: 2,
“adjustment_negative”: 1
}
}