code: function outward_act_cache(ctxt, data) {
    Assert(ctxt.options)
  
    var so = ctxt.options
    var res = data.res
    var meta = data.meta
  
    var actid = meta.id
    var private$ = ctxt.seneca.private$
  
    if (actid != null && so.history.active) {
      var actdetails = private$.history.get(actid)
  
      if (actdetails) {
        actdetails.result.push({ when: Date.now(), res: res })
      }
    }
  }
docs: Store result in action cache TODO: replace with history