@Override
    public void beginResponse(OutputStream outputStream) throws IOException {
        generator = generatorFactory.createGenerator(outputStream, JsonEncoding.UTF8);
        generator.setRootValueSeparator(new SerializedString(""));
    }
A Server-Sent Events (SSE) renderer for asynchronous events such as
tokens from a language model.

@author lesters
container-search/src/main/java/com/yahoo/search/rendering/EventRenderer.java