fix(library): canonicalize page parameter on the article reader
The library article detail page (one text page per pagination page) did not redirect for non-canonical ?page values (e.g. ?page=0 silently showed page 1). Build the Pagination from the raw request page and apply PaginationGuard so page=1/junk are stripped and out-of-range pages redirect to the last page, matching the other paginated lists.