Option to prefer upstream dev over prod regardless of freshness

[rossellatoma]

Hi! we've noticed an edge case with the current upstream selection logic.

At the moment, the package defaults to using upstream prod if its data appears fresher than upstream dev. While this makes sense in many cases, we'd like to have the option to prefer upstream dev, even when it's not the freshest.

To support this, we introduced an additional variable - upstream_prod_prefer_dev — and modified the ref macro to default to dev when this flag is set.

Has this use case come up before? Curious if there’s already a pattern or config we missed.

Thanks!