Let a module read its own streams back by a batch direct get, as it reads its log, so its tools can answer what the stream holds (a build step's whole failure output)

node-tools/internal/launch/event_answer_test.go

@@ -38,6 +38,7 @@ func (b *subscribing) Publish(json.RawMessage) error                          {
 func (b *subscribing) Ask(json.RawMessage) (json.RawMessage, error)           { return nil, nil }
 func (b *subscribing) State(string, json.RawMessage) (json.RawMessage, error) { return nil, nil }
 func (b *subscribing) Log(string, json.RawMessage) (json.RawMessage, error)   { return nil, nil }
+func (b *subscribing) StreamRead(json.RawMessage) (json.RawMessage, error)    { return nil, nil }
 func (b *subscribing) Watch(json.RawMessage, func(json.RawMessage) error) (func(), error) {
 	return func() {}, nil
 }