Creates an alteration package for an application. If the application already has a pending alteration package with the same key and the same data, the new package supersedes it: the existing package is archived and the new one has refreshed_from_alteration_package_id set to it. This only happens when the application is pending and the caller also has permission to archive application alteration packages. Otherwise, or if another request creates the identical package at the same time, no new package is created: the existing pending package is returned unchanged if it was created in the last minute, and an older one gets a 409 naming it. When the product module returns several alteration packages, all of them are created, and they are never matched against or returned in place of another package.
Another request superseded, archived or applied the matching pending application alteration package first. Also returned when auto_apply is true and an existing pending alteration package with the same key and data would be returned; it is not applied, and can be applied by its ID. Also returned when that existing package was created more than a minute ago.