Final task of PR2 DRY pass. Extracts the verbatim
`offset + items.length >= total` math repeated across 8
createInfiniteQuery sites into a single Page<T>-shape helper.
The task spec described a bare-array helper signature
(lastPage: T[], pageSize-based stop), but no call site in this
repo uses that shape — every paged endpoint returns a Page<T>
envelope. The helper is named pageGetNextPageParam and matches
the actual canonical shape so the 8 copies could collapse.
Migrated:
- likes.ts: 3 sites (TrackRef, AlbumRef, ArtistRef)
- albums.ts: 1 site (AlbumRef)
- queries.ts: 4 sites (artists + 3 search facets)
history.ts left alone — uses has_more/total, different shape.
bvandeusen
