A document-preview / attachment-thumbnail loading state reproducing a Group 3 fax handshake and page transmission: two waveform-rendered handshake tones, then the page builds in as horizontal scan lines top to bottom, with one deliberate paper-slip shear partway down the frame before the lines resume true.
pnpm dlx shadcn@latest add "https://design.helpmarq.com/r/fax-line-slip.json"