feat: use availability rate overrides in calendar tooltip and booking modal

- Load rate_overrides in CalendarPage, pass as priceOverrides to BookingCalendar
- Tooltip shows override price for the hovered date (falls back to baseRate)
- BookingModal sums per-night prices from overrides for the stay period
- Room baseRate now only used as initial default for availability grid

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/components/bookings/BookingModal.tsx

@@ -31,6 +31,8 @@ const HOURS = Array.from({ length: 24 }, (_, i) => i)
 interface BookingModalProps {
   open: boolean
   draft: DraftBooking
+  /** categoryId → date (YYYY-MM-DD) → price; used to price bookings by availability rates */
+  priceOverrides?: Record<string, Record<string, number>>
   rooms: Room[]
   bookings?: Booking[]
   onClose: () => void
@@ -94,7 +96,7 @@ function getRoomCategories(rooms: Room[], bookings: Booking[], checkIn: string,
   })
 }
 
-export function BookingModal({ open, draft, rooms, bookings = [], onClose, onSave, existing, rentalObjects, rentalBookings = [], onRentalSave, slug }: BookingModalProps) {
+export function BookingModal({ open, draft, rooms, bookings = [], onClose, onSave, existing, rentalObjects, rentalBookings = [], onRentalSave, slug, priceOverrides }: BookingModalProps) {
   const { statuses } = useModules()
   const { user } = useAuth()
   const tvEnabled = statuses['tv-welcome'] === 'active'
@@ -329,9 +331,22 @@ export function BookingModal({ open, draft, rooms, bookings = [], onClose, onSav
     : 0
 
   const hourlyHours = Math.max(0, endHour - startHour)
+  // Calculate room cost: sum per-night prices from availability overrides, fall back to baseRate
+  const roomNightlyTotal = (() => {
+    if (!room || !form.checkIn || !form.checkOut || nights <= 0) return 0
+    const catId = room.categoryId
+    const catOverrides = catId ? priceOverrides?.[catId] : undefined
+    if (!catOverrides) return (room.baseRate ?? 0) * nights
+    let sum = 0
+    for (let i = 0; i < nights; i++) {
+      const d = format(addDays(new Date(form.checkIn), i), 'yyyy-MM-dd')
+      sum += catOverrides[d] ?? room.baseRate ?? 0
+    }
+    return sum
+  })()
   const roomBaseTotal = isHourly && room?.allowHourly
     ? (room.hourlyRate ?? 0) * hourlyHours
-    : (room?.baseRate ?? 0) * nights
+    : roomNightlyTotal
   const discountAmount = selectedDiscount
     ? selectedDiscount.valueType === 'percent'
       ? Math.round(roomBaseTotal * Math.min(100, selectedDiscount.value) / 100)