* remove the experimental web vital hook api
* remove the exported flush effects api and only error on development, keep only usage to styled-jsx
for web vital hook API: The usage is not widly adopted since the existing exported vital api could do the same work. In the future we'll deprecate the `_app.server` in favor of `_app` in server component pages. so that this api won't be required.
for flush effects api: other css-in-js libs are not using the same approach like styled-jsx which holding a style registry and could flush it during streaming. emotion-js and styled-components are still relying on `Document.getInitialProps` atm and we have supported it in latest canary
* Update rsc refresh typing and doc example
* Update docs/api-reference/next/streaming.md
Co-authored-by: Shu Ding <g@shud.in>
Co-authored-by: Shu Ding <g@shud.in>
Implements https://github.com/vercel/next.js/issues/30997 with some minor tweaks to the design:
* The hook is moved to Client Components (e.g. `pages/_app` instead of `pages/_document`). This was a silly oversight in the original design: the hook needs to be called during server prerendering.
* `useFlushEffects` instead of `useFlushEffect` as there isn't a particularly safe way to implement the singular semantics as a Client Component hook given the current implementation of server rendering.
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Fixes#30997
Move undocumented `next/rsc` and `next/vitals` to `next/streaming`. In the future `next/streaming` can contain streaming SSR related (including react server components) APIs together.
