As a data maintainer I want to be able to find problematic values that have a explicitly defined bound but should not. I want to be able to define per property if it should take bounds or not.
We should have a new constraint type No bounds for quantity properties that are about non-physical quantities without uncertainty. This is in fact a substantial fraction of Wikidata quantity properties. Since use of bounds indicates uncertainty and we cannot use novalue for bounds, we need to indicate the absence of uncertainty by using no bounds at all, rather than ±0 bounds.
Transferred to phabricator from wikidata.
See README for the steps to add a new constraint type.