docs: runtime prefetching -> optimizing prefetching (#96934)
With the latest GA changes, when using Cache Components with Partial
Prefetching:
> prefetch={true} turns on prefetching
These changes try to align around that idea.
- runtime prefetching guide is now about optimizing
- various changes in prose across docs
- even fix an error page for pages router, which had a broad title
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Co-authored-by: Aurora Scharff <aurora.sofie@gmail.com>
(cherry picked from commit ec1a44d0f112d7a3dd7ce5138ddde19a3a1a876b)
