Fix critical blockers in passenger count selector feature

CRITICAL ISSUE #1: Callback Signature Mismatch
- Updated handleRouteSearch callback to include passengers parameter
- Added passengers to params encoding in navigation state
- Updated OnlineBoardFilterProps to include passengers in initialSearchParams

CRITICAL ISSUE #2: Missing Validation on initialPassengers
- Added validatePassengerCounts function to validate and sanitize passenger counts
- Ensures all values are in valid range (0-9) and total doesn't exceed 9
- Updated state initialization to use validated passenger counts
- Removed unnecessary type assertion from handleSearch callback

Changes:
- online-board-filter.tsx: Updated callback signature and params encoding
- route-filter.tsx: Added passenger validation function and updated state init

apps/react/src/app/features/online-board/components/online-board-filter.tsx

@@ -14,6 +14,7 @@ interface OnlineBoardFilterProps {
     returnDate?: string | Date
     flightNumber?: string
     tripType?: string
+    passengers?: { adults: number, children: number, infants: number }
   }
 }
 
@@ -28,7 +29,7 @@ export const OnlineBoardFilter: React.FC<OnlineBoardFilterProps> = ({ initialSea
     navigate(`/onlineboard/flight/${params}`)
   }
 
-  const handleRouteSearch = (departure: string, arrival: string, date: Date, returnDate?: Date | null, tripType?: string) => {
+  const handleRouteSearch = (departure: string, arrival: string, date: Date, returnDate?: Date | null, tripType?: string, passengers?: { adults: number, children: number, infants: number }) => {
     // Navigate to route search results
     const params = btoa(JSON.stringify({
       departure,
@@ -36,6 +37,7 @@ export const OnlineBoardFilter: React.FC<OnlineBoardFilterProps> = ({ initialSea
       date: date.toISOString(),
       ...(returnDate && { returnDate: returnDate.toISOString() }),
       ...(tripType && { tripType }),
+      ...(passengers && { passengers }),
     }))
     navigate(`/onlineboard/route/${params}`)
   }
@@ -63,6 +65,7 @@ export const OnlineBoardFilter: React.FC<OnlineBoardFilterProps> = ({ initialSea
             initialDate={initialSearchParams?.date}
             initialReturnDate={initialSearchParams?.returnDate}
             initialTripType={initialSearchParams?.tripType}
+            initialPassengers={initialSearchParams?.passengers}
           />
         </AccordionTab>
       </Accordion>

apps/react/src/app/features/online-board/components/route-filter.tsx

@@ -23,6 +23,23 @@ export interface RouteFilterProps {
 }
 
 // Validation service
+const validatePassengerCounts = (passengers?: PassengerCounts): PassengerCounts => {
+  if (!passengers) return { adults: 1, children: 0, infants: 0 }
+
+  const safe = {
+    adults: Math.max(0, Math.min(9, Math.floor(passengers.adults || 0))),
+    children: Math.max(0, Math.min(9, Math.floor(passengers.children || 0))),
+    infants: Math.max(0, Math.min(9, Math.floor(passengers.infants || 0))),
+  }
+
+  // Ensure total doesn't exceed 9
+  const total = safe.adults + safe.children + safe.infants
+  if (total > 9) {
+    return { adults: Math.min(9, safe.adults), children: 0, infants: 0 }
+  }
+  return safe
+}
+
 const validateCityCode = (code: string | undefined): boolean => {
   if (!code) return false
   return /^[A-Z]{3}$/.test(code.toUpperCase())
@@ -63,6 +80,7 @@ export const RouteFilter: React.FC<RouteFilterProps> = ({
   initialPassengers
 }) => {
   const { t } = useTranslation()
+  const validated = validatePassengerCounts(initialPassengers)
   const [departure, setDeparture] = useState<City | null>(getCityByCode(initialDeparture))
   const [arrival, setArrival] = useState<City | null>(getCityByCode(initialArrival))
   const [date, setDate] = useState<Date | null>(
@@ -80,9 +98,9 @@ export const RouteFilter: React.FC<RouteFilterProps> = ({
   )
   const [startTime, setStartTime] = useState('00:00')
   const [endTime, setEndTime] = useState('23:59')
-  const [adults, setAdults] = useState(initialPassengers?.adults || 1)
+  const [adults, setAdults] = useState(validated.adults)
-  const [children, setChildren] = useState(initialPassengers?.children || 0)
+  const [children, setChildren] = useState(validated.children)
-  const [infants, setInfants] = useState(initialPassengers?.infants || 0)
+  const [infants, setInfants] = useState(validated.infants)
   const [showPassengerDropdown, setShowPassengerDropdown] = useState(false)
 
   const totalPassengers = adults + children + infants
@@ -102,8 +120,7 @@ export const RouteFilter: React.FC<RouteFilterProps> = ({
   const handleSearch = useCallback(() => {
     if (validateRouteParams(departure, arrival, date) && onSearch) {
       // Pass all search parameters including return date for round trips and passenger counts
-      const handler = onSearch as (departure: string, arrival: string, date: Date, returnDate?: Date | null, tripType?: string, passengers?: PassengerCounts) => void
+      onSearch(departure!.code, arrival!.code, date!, returnDate, tripType, { adults, children, infants })
-      handler(departure!.code, arrival!.code, date!, returnDate, tripType, { adults, children, infants })
     }
   }, [departure, arrival, date, returnDate, tripType, adults, children, infants, onSearch])