Library cards in the studio were read-only. Their preview now renames a
saved prompt (tags kept) or deletes it to the Recycle Bin, and any card
can be dragged out of the drawer onto a canvas prompt box (outlined,
previewed, one undo step) or onto empty canvas for a prompt node; over
the drawer the drag passes through to the assembly board.
The preview moved to ui_prompt_card_popover.js (the deck goes from 751 to
480 lines) and the canvas drag is prompt_card_drag.js; material_drag.js
takes passThrough and effectAllowed, prompt_drop.js a known-text drag.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
