Add "from service worker" flag on network response events

[juliandescottes]

CDP supports a boolean flag on network.Response called fromServiceWorker, which indicates if the request was handled by a service worker.

There are tests for this in both puppeteer and playwright test suites, so it might be worth adding to WebDriver BiDi?

I don't think the current initiatorType and destination can be used to workaround this. There is a "serviceworker" destination in the spec, but it's only used when loading a worker script to be used as a service worker.