Brief Summary
When creating a recipient record in this Gadget Shopify app, the shopId foreign key field is saved as null in the database despite being set correctly in the action code. This causes the error "Cannot return null for non-nullable field Recipient.shop" when trying to view or edit recipients. After 9 different attempted fixes using various Gadget framework approaches (applyParams, save(), api.internal, manual field setting, relationship manipulation), the issue persists, suggesting a fundamental framework-level bug with how belongsTo fields marked as parent relationships are handled in create actions.
Attached is a detailed doc explaining what we tried so far