Numpad Modal In progress

Terminal numpad modal (1:1 from numpad-modal-spec). Generic numpad-input shell driving porsiya / guest count / receipt lookup / weight / discount. Header (#35325E, configurable title) + one of three display modes (A value + ₼ chip / B value-only / C search input) + 4×3 numpad (white keys on #F2F4F5 tray, 2px gaps, backspace) + action row (Cancel + configurable CTA: Add/Save/Return, disabled #C4C4CC → active #2684FF with check). Radius 8px, Inter, all colours/space/type bound to design tokens.