next.js

b83417d2 - Add `writeInitialFullyStaticResponseIntoCache` for the initial HTML

Add `writeInitialFullyStaticResponseIntoCache` for the initial HTML The initial HTML of fully static pages should be cached with `FetchStrategy.Full` and `isResponsePartial = false`, since all segments are present and no dynamic follow-up is needed. Previously, `writeStaticStageResponseIntoCache` was used for both navigation responses and initial HTML, but its `FetchStrategy.PPR` + `isResponsePartial = true` settings caused issues with mismatching prefetch rewrites — partial entries triggered unnecessary dynamic follow-up requests. `writeStaticStageResponseIntoCache` is now used only for navigation responses (static stage of PPR).