Unused `searchParams` in `"use cache"` page should not cause dynamic (#75662)
When `dynamicIO` is not enabled, and only the standalone `useCache`
experimental flag is enabled, we can not encode `searchParams` as
hanging promises. To still avoid unused search params from making a page
dynamic (due to the `searchParams` being encoded into the cache key), we
set them to a promise that resolves to an empty object, while also
overwriting the to-be-invoked function for generating a cache entry with
a function that creates an erroring `searchParams` prop before invoking
the original function. This ensures that used `searchParams` inside of
cached functions would still yield an error.
closes NAR-85
next.js
ae5026a0 - Unused `searchParams` in `"use cache"` page should not cause dynamic (#75662)
