next.js

aec75c2f - fix: build stats should properly report root page size in appDir (#51854)

fix: build stats should properly report root page size in appDir (#51854) ### What? `next build` is incorrectly reporting file size stats for the root path when using the app dir ### Why? In #50768, the denormalization logic was removed for appDir routes, but `pagesManifest` has the root page keyed by `/` while the actual path will be `/index`. ### How? This re-adds a simpler denormalize function that just replaces `/index` with `/`. semi-related: #42819 Fixes #51692 link NEXT-1306 --------- Co-authored-by: JJ Kasper <jj@jjsweb.site> Co-authored-by: Jiachi Liu <inbox@huozhi.im>