Schedule per-leg operator logos + Купить button

- FlightCard: when the flight is multi-leg, render one OperatorLogo
  per leg in the header so code-share / multi-carrier journeys show
  both airline brands (Angular's `operator-logo-and-model x N` row).
  Direct flights keep the single logo.
- FlightCard: add an orange "Купить" (buy ticket) link rendered next
  to "Детали рейса" when the card is in the schedule context. Links
  to aeroflot.ru's booking flow per Angular's flight-actions wiring.
- Reverted earlier per-leg flight-number stack — IFlightLeg in React
  doesn't carry a per-leg flightId, so the parent SU number is the
  authoritative label. The Angular dual-number stack belongs to the
  ConnectingFlight shape (separate from MultiLeg) which the React
  code already renders flat.

src/ui/flights/FlightCard.scss

@@ -199,6 +199,21 @@
     }
   }
 
+  &__buy-btn {
+    background: #ff9000;
+    color: #fff;
+    border: none;
+    border-radius: 4px;
+    padding: 10px 24px;
+    font-size: 14px;
+    font-weight: 500;
+    cursor: pointer;
+    text-decoration: none;
+    transition: background-color 150ms ease;
+
+    &:hover { background: #e68200; }
+  }
+
   &__details-btn {
     background: colors.$blue;
     color: #fff;

src/ui/flights/FlightCard.tsx

@@ -96,6 +96,7 @@ export const FlightCard: FC<FlightCardProps> = ({
 
   const flightNumber = `${flight.flightId.carrier} ${flight.flightId.flightNumber}`;
   const carrier = operatingCarrier(flight.operatingBy) ?? flight.flightId.carrier;
+  const isMultiLeg = flight.routeType === "MultiLeg";
   const aircraftName =
     departureLeg.equipment?.aircraft?.actual?.title ??
     departureLeg.equipment?.aircraft?.scheduled?.title ??
@@ -171,7 +172,15 @@ export const FlightCard: FC<FlightCardProps> = ({
         </div>
 
         <div className="flight-card__operator">
-          <OperatorLogo carrier={carrier} locale={language} />
+          {isMultiLeg
+            ? flight.legs.map((leg, i) => (
+                <OperatorLogo
+                  key={`${operatingCarrier(leg.operatingBy) ?? carrier}-${i}`}
+                  carrier={operatingCarrier(leg.operatingBy) ?? carrier}
+                  locale={language}
+                />
+              ))
+            : <OperatorLogo carrier={carrier} locale={language} />}
         </div>
 
         <div className="flight-card__time">
@@ -335,6 +344,18 @@ export const FlightCard: FC<FlightCardProps> = ({
               >
                 <img src="/assets/img/share.svg" alt="" aria-hidden="true" />
               </button>
+              {direction === "schedule" && (
+                <a
+                  className="flight-card__buy-btn"
+                  data-testid="flight-buy-button"
+                  href="https://www.aeroflot.ru/sb/app/ru-ru"
+                  target="_blank"
+                  rel="noopener noreferrer"
+                  onClick={(e) => e.stopPropagation()}
+                >
+                  {t("SHARED.BUY-TICKET") || "Купить"}
+                </a>
+              )}
               <button
                 type="button"
                 className="flight-card__details-btn"