The Studio drew the page after a held edit or cover change by running the
card's operations on its own book, which knows nothing of the journey's
photos, words and figures, so a caption from a photo, a text from an entry
or a map from the route came out differently or not at all. The card now
carries the page the server's trial made with the full context, read with
the book's schema and within the card's size, and the Studio draws it while
its book stands at the version the trial ran on. A book that moved on, a
card from before and a page too heavy to carry still run the operations on
the book on screen, the book the change will run on. The receipt leaves the
page out, since an applied change is drawn from the book itself.
Changes held in one step are applied in the order the chat shows them, so
"undo all" walks them back newest first. A page put back is checked against
the digest of the page as the change left it, so a save to another page no
longer blocks the undo; restore_book_page takes these digests as an option and
keeps the whole book check without them. The book card counts the user's own
photos, the preview tool describes itself per role, a copy into another trip
names no places, a held vacay toggle says up front whether it can be taken
back, and a viewer's Studio prompt names none of the design's tools.
The book card e2e calls the book services inside a request context, the
preview expects the design id beside the operations, a trial without a book
has no version, the JPEG fixture keeps its signature, and the upload test
checks the file name where the client sets it.
Maurice