docs: outlining and lcp (#96942)
LCP can be affected if the LCP element is sitting within a Suspense
boundary, even if its nothing but static content, if the static content
is "too large".
Apps should prefer, as long as possible, to not have a Suspense boundary
around the LCP element.
-
https://react.dev/reference/react/Suspense#what-activates-a-suspense-boundary
> Waiting for a large boundary’s HTML to arrive during streaming server
rendering. Sending HTML takes time, so a boundary with enough content
activates even when nothing in it suspends. React reveals the content as
the HTML arrives.
