Initial abstract classes

[karaggeorge]

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[karaggeorge]

Might also need to add abstract methods for getting a cookie/all cookies. I know that in the web side, we'll have to do some extra implementation for Set-Cookie headers, so we might also have to inject some cookies into the request, but not 100% sure if needed yet

[shuding]

I think that's already handled by

next.js/packages/next/server/base-server.ts

Line 370 in 0f7f332

setLazyProp({ req: req as any }, 'cookies', getCookieParser(req.headers))

so might not needed in the base class right now.

[karaggeorge]

This will behave same as Node response. This promise will resolve when send is called with a Response object that has the headers/status at that moment, but the body will still be able to be streamed.

To match 100%, we could add a call to send within the transform stream when the first write happens, but since we'll only be using streams in render.tsx we can just call send there manually for simplicity

[karaggeorge]

Closing in favor of #32999