add ARIA labels, pressed states, and fix keyboard visibility across card detail components

src/components/card-detail/PriorityPicker.tsx

@@ -27,6 +27,7 @@ export function PriorityPicker({ cardId, priority }: PriorityPickerProps) {
           <button
             key={value}
             onClick={() => updateCard(cardId, { priority: value })}
+            aria-pressed={priority === value}
             className={`rounded-full px-3 py-1 text-xs font-medium transition-all ${
               priority === value
                 ? "text-white shadow-sm"