fix(admin): polish orders

Same gap as products/categories: table select-all and per-row select
checkboxes had no accessible name. Added aria-label (row label
includes order number for context). New adminOrders.selectAllRows/
selectRow keys across en/ru/hy.

Order detail page and order-timeline component reviewed — no
interactive checkboxes or focus-visible gaps found there.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

src/app/i18n/ru.ts

@@ -1287,6 +1287,8 @@ export const ru: Translations = {
     back: 'Назад к заказам',
     search: 'Поиск по номеру заказа, имени, email или телефону…',
     export: 'Экспорт',
+    selectAllRows: 'Выбрать все заказы',
+    selectRow: 'Выбрать заказ',
     view: 'Просмотр',
     orderNumber: 'Заказ',
     customer: 'Клиент',