Item 1: ArrowLeft/Right/Up drive nope/like/maybe through commit(); ArrowDown
and Backspace (kept alias) drive undo(); Esc closes the top open sheet only
(viewer -> dossier -> deck, inert on report). Text inputs/TEXTAREA/SELECT/
contentEditable swallow keys; arrow defaults are prevented (no page scroll).
Item 2: card center tap now opens the dossier (bike data first); side taps
keep flipping photos; the direct card -> viewer door is retired. The deck
dossier records its pile entry; the hero tap opens the viewer with a
backToDetail chain so Esc walks viewer -> dossier -> deck (repeatable).
Item 3: deck card + dossier hero photos switch from cover to contain over a
soft blurred backdrop of the same image (option C, demo panel C); thumb and
fullscreen viewer untouched; nophoto paths render no backdrop.
e67f8a0cda