### What
When a prefetch cache entry becomes "stale", it'll remain stale until
eventually it gets evicted. However during that stale window, the cache
is never revalidated, and so instant navigations stop working and data
is fetched from origin every navigation.
### Why
The `lastUsedTime` entry on the prefetch cache is currently only updated
after the first read. Once it becomes stale, `applyFlightData`'s
recursive functions will see that there is no longer a reusable prefetch
cache entry, and will trigger a lazy fetch of the new data on every
subsequent navigation.
### How
This updates prefetch cache handling to always ensure we’re using a
fresh or reusable prefetch cache entry. This means that stale prefetch
entries will be refreshed on a navigation event. As a result of this,
I’ve had to disable one of our tests that relies on this stale cache
behavior. It’s not ideal that we’re blocked on the loading boundary when
fetching child segment data—ideally we can refactor this to cache the
loading component in the CacheNode and copy it over on navigations,
similar to how ‘head’ is handled. I’ll work on this in a separate PR.
Note: The new client cache test for this is disabled in PPR for the same
reason as the other tests: auto prefetching with PPR navigations is
currently loading fresh data rather than reusing the prefetch cache.
Fixes#58969Fixes#58723
Closes NEXT-1904
d371f648d2