Deprecate Oniguruma package #448
Description
The repository for Oniguruma was deprecated on 2025-04-24, with an announcement that the project has ended. Today, its only depended on by jq (see also, upstream jq issue: jqlang/jq#3313)
We should mark the package for Oniguruma as deprecated / unsupported to encourage folks to use an actively-maintained alternative instead. (Today, neither Brioche nor the registry has the concept of a "deprecated" package, so we'll likely need a new feature implemented to resolve this issue)