The web shell queues the page's calls as control requests (the channel the desktop control server uses) and answers them on the next frame. The API is installed in every mode; opening, saving, the file name and the unsaved flag stay with the host messages.
The transports, the message types and the origin checks come from the shared crate (storytold/craft-libs#420). `data-host="page"` on the canvas now hosts DeckCraft in a page's own document, as in the other apps; the parent bridge keeps its behaviour.
A same-origin page that frames DeckCraft's web build with ?host=parent
sends a file with deckcraft:open and gets every save back as
deckcraft:save {name, saveAs, bytes} instead of a download, with
deckcraft:ready, deckcraft:dirty and deckcraft:failed, as GridCraft,
WordCraft and PdfCraft do. Without ?host=parent nothing changes.
Save follows the desktop app. Every file from the page opens through
file.adopt like File > Open on the desktop; a presentation sent with a
presentation name keeps that name as its file, so Save (Ctrl+S, the
File tab, the Close prompt or the command palette) writes it back under
that name and format with saveAs: false. Anything else (no name, an
outline, a damaged file opened as a repaired copy, a dropped file) is
untitled, and its first Save is a new <title>.deckcraft with saveAs:
true, as is Save As. Exports and Print are copies (saveAs: false).
Host mode starts with an empty presentation that gives way to the first
file while untouched, &author= signs comments, and the URL flags are
read as whole parameters so a free-text author can't set ?show.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Helen Kwok