feat(bookings): implement booking system and confirmation flow

Add database tables and repository for managing bookings
Create API endpoints for booking submission and capacity management
Update landing page to persist bookings before WhatsApp redirection

server/api/public/bookings.post.ts

@@ -0,0 +1,56 @@
+import type { BookingMode, CreateBookingResponse, TicketType } from '~~/shared/booking'
+
+import { getTicketCatalogItem, getSeatCount } from '~~/shared/booking'
+
+import { buildAppUrl } from '../../utils/app-url'
+import { createBooking } from '../../utils/booking-repository'
+import { buildBookingMessage, parseCreateBookingInput } from '../../utils/bookings'
+import { assertBadRequest } from '../../utils/http'
+import { getPublicContactById } from '../../utils/user-repository'
+
+export default defineEventHandler(async (event): Promise<CreateBookingResponse> => {
+  const body = await readBody<{
+    customerName?: string
+    customerPhone?: string
+    bookingMode?: BookingMode
+    quantity?: number
+    ticketType?: TicketType
+    personInChargeId?: string
+  }>(event)
+
+  const input = parseCreateBookingInput(body)
+  const personInCharge = await getPublicContactById(input.personInChargeId)
+
+  assertBadRequest(personInCharge, 'Selected person in charge is not available')
+
+  const ticket = getTicketCatalogItem(input.ticketType)
+
+  assertBadRequest(ticket, 'Ticket category is invalid')
+
+  const seatCount = getSeatCount(input.bookingMode, input.quantity)
+  const totalPrice = seatCount * ticket.price
+
+  const { booking, confirmationToken } = await createBooking({
+    customerName: input.customerName,
+    customerPhone: input.customerPhone,
+    bookingMode: input.bookingMode,
+    quantity: input.quantity,
+    seatCount,
+    ticketType: input.ticketType,
+    unitPrice: ticket.price,
+    totalPrice,
+    personInChargeId: personInCharge.id,
+    personInChargeName: personInCharge.fullName,
+    personInChargePhoneNumber: personInCharge.phoneNumber
+  })
+
+  const confirmationUrl = buildAppUrl(event, `/confirmation/${confirmationToken}`)
+  const whatsappMessage = buildBookingMessage(booking, confirmationUrl)
+  const whatsappUrl = `https://wa.me/${booking.personInChargePhoneNumber}?text=${encodeURIComponent(whatsappMessage)}`
+
+  return {
+    booking,
+    confirmationUrl,
+    whatsappUrl
+  }
+})