Consider short-circuiting in case a sync processor returns js/Error

[arichiardi]

This is a tough one and I haven't made up my mind yet.

Basically the use case is that, let's say we have a processor that instead of throwing a js/Error just returns it, like:

(defn validate-data
  [ctx]
  (let [data (:some-data ctx)
        spec ::some/spec]

    (if (not (s/valid? spec data))
      (ex-info "Invalid data" {})
      data)))

Then fonda at the moment does not short-circuits and errors out. We only short circuit in case of anomaly data.

Maybe it makes sense but I just want to note this down for future reference.

Also, should it write this in the docs?