egui's paste event only carries text, so a clipboard holding just a picture
sent no paste at all on Ctrl+V, and the ribbon/context-menu Paste only knew
WordCraft's own copy ("the clipboard is empty").
Desktop: the app reads the clipboard's picture through a new
Services::clipboard_picture (arboard, already in the build via egui-winit):
copied files first, else image pixels. Mod+V whose release arrives without a
paste event, and Paste from the ribbon or menus, insert that picture through
insert.picture (one undo step); text naming copied picture files inserts the
pictures. Pixel sizes are hostile: at most 16,000 px a side and 50 Mpx, the
buffer must match, files at most 200 MB.
Web: a document paste listener reads image files from the paste event when
there's no text and delivers them through the inbox like dropped pictures.
Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: Brandon Thomas <echelon@gmail.com>