NewPredictorStreamSource returns a new PredictorSource based on a persistent event stream.

NewWatchPredictorSource returns a new PredictorSource based on a refresh-and-watch PredictorWatcher implementation.

Both UPDATE and DELETE events are expected to have a Predictor containing the corresponding resourceVersion.

PredictorSource provides a registry of Predictors along with a channel of update events corresponding to the Predictors.