.arcconfig

obsolete: explicitly pass relation items to effectflag computation

To track folds, we are about to change the content of `rel`. To simplify this
change, we update the `geteffectflag` function beforehand.

{
    "conduit_uri": "https://phab.mercurial-scm.org/api",
    "repository.callsign": "HG",
    "arc.land.onto.default": "@",
    "base": "hg:.^"
}