Feature request: @scope input should default to the scope specified in package.json

[jasonkarns]

As I've used the setup-node action in about a dozen projects now, I've consistently needed to set the scope input for the action. This seems redundant because this information is already present in the package.json in the name.

When this action is used to publish a node module to a registry, the scope must be the same as the one defined in the package's package.json. Information that must change together is precisely the kind of information that should be DRY. So I would hope that the scope input could be defaulted to the scope defined in the package.json automatically.

(The same should be true for the registry, as defined in package.json#publishConfig)

[jasonkarns]

I wished for this behavior back in 2020 and I wish for it even more now.

It's quite frustrating to try and use setup-node in a reusable workflow, when the scope name must then be parameterized. This information already exists in the package.json. If this action would respect the scope from package.json, then there would be no need for an explicit scope parameter to the action. Which then means, setup-node could be more easily used in reusable workflows without needing to parameterize the workflow with redundant params.