feat: room/rental tabs in booking modal + smart time slot filtering

BookingModal:
- Add 'Номер' / 'Аренда объекта' tabs when rental objects exist
- Rental tab: object picker, date, full-day toggle, conflict-aware time dropdowns, guest/phone fields, total amount

RentalBookingModal:
- Filter start times: exclude hours inside booked slots + bufferMinutes gap
- Filter end times: cap at next booking's start hour
- Disable 'Весь день' if any timed bookings exist for the day
- Show 'Все слоты заняты' when no start hours are available
- Show buffer duration in time section label

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

src/components/calendar/BookingCalendar.tsx

@@ -741,6 +741,10 @@ export function BookingCalendar({ rooms, bookings, slug, onBookingCreate, onBook
           draft={bookingModalDraft}
           rooms={rooms}
           bookings={bookings}
+          slug={slug}
+          rentalObjects={rentalObjects}
+          rentalBookings={rentalBookings as unknown as import('../../data/rentalData').RentalBooking[]}
+          onRentalSave={rb => { onRentalBookingCreate?.(rb); setBookingModalDraft(null) }}
           onClose={() => {
             if (bookingModalDraft) onDraftCancel?.(bookingModalDraft.roomId)
             setBookingModalDraft(null)