OnlineBoard search: render Купить/Онлайн регистрация in expanded row

Angular's board search results expansion shows [Купить] [Онлайн
регистрация] [Детали рейса]. React only rendered Details. Added a
`renderActions` prop on FlightCard/FlightList so the feature layer
can inject extra buttons without the ui layer importing from
features. OnlineBoardSearchPage wires it to FlightActions with
showShare=false (the row already has a dedicated share icon).

Visibility rules fall through to canBuyTicket / canRegister (same
as BoardDetailsHeader), so cancelled/past flights still hide the
Buy button and carriers without a registrationUrl still hide the
Online Registration button — matching Angular's per-flight gating.

Integration test mocks useAppSettings to avoid requiring the real
ApiClientProvider in flight-search.test.tsx.

src/features/online-board/components/OnlineBoardSearchPage.tsx

@@ -18,6 +18,7 @@ import { useNavigate } from "@modern-js/runtime/router";
 import { useLocale } from "@/i18n/useLocale.js";
 import { useTranslation } from "@/i18n/provider.js";
 import { FlightList } from "@/ui/flights/FlightList.js";
+import { FlightActions } from "./BoardDetailsHeader/FlightActions.js";
 import { findClosestFlightId } from "../closestFlight.js";
 import { PageLayout } from "@/ui/layout/PageLayout.js";
 import { PageTabs } from "@/ui/layout/PageTabs.js";
@@ -514,6 +515,18 @@ export const OnlineBoardSearchPage: FC<OnlineBoardSearchPageProps> = ({
               onFlightClick={handleFlightClick}
               initialCurrentFlightId={initialCurrentFlightId}
               direction={params.type}
+              renderActions={(flight) => (
+                // Mirrors Angular's board search expansion: each row
+                // shows [Купить] [Онлайн регистрация] alongside the
+                // Details button. Visibility falls through to the
+                // same canBuyTicket / canRegister rules we use in the
+                // BoardDetailsHeader.
+                <FlightActions
+                  flight={flight}
+                  locale={language}
+                  showShare={false}
+                />
+              )}
             />
           </section>
         )}