stream: deprecate writable/readable

Doc deprecate writable/readable
Remove usage of writable/readable from core. Leave it just for user land compat.

EDIT: Updated description. Old description remains below.

Details

I think there is a potential issue with `'end'` not being emitted despite the `IncomingMessage` being `readable`. We've encountered this here https://github.com//pull/29376. There are fixes pending (https://github.com//pull/27984) for the observed behaviour of this (at least in terms of emitted events). But I think it might be worth investigating why `'end'` is not emitted despite readable being true.

fastify/fastify#1833 is also relevant.