feat(bookings): add transaction document uploads for bank payments

Add payment method selection (Cash/Bank) to booking details
Support uploading, downloading, and deleting transaction documents
Update database schema and API endpoints to handle file storage

server/api/bookings/[id]/transaction-document.get.ts

@@ -0,0 +1,35 @@
+import { sendStream, setHeader } from 'h3'
+
+import { requireAuth } from '../../../utils/auth'
+import { getBookingTransactionDocument } from '../../../utils/booking-repository'
+import { getRequiredRouteParam, httpError } from '../../../utils/http'
+import {
+  getSafeDownloadName,
+  getTransactionDocumentFile
+} from '../../../utils/transaction-documents'
+
+export default defineEventHandler(async (event) => {
+  const auth = await requireAuth(event)
+  const bookingId = getRequiredRouteParam(event, 'id', 'Booking ID')
+
+  const document = await getBookingTransactionDocument({
+    bookingId,
+    personInChargeId: auth.user.role === 'super_admin' ? undefined : auth.user.id
+  })
+
+  if (!document) {
+    httpError(404, 'Transaction document not found')
+  }
+
+  const file = await getTransactionDocumentFile(document.storageName)
+  const downloadName = getSafeDownloadName(document.originalName)
+
+  setHeader(event, 'content-type', document.mimeType)
+  setHeader(event, 'content-length', String(file.size))
+  setHeader(event, 'content-disposition', `attachment; filename="${downloadName}"`)
+  setHeader(event, 'x-content-type-options', 'nosniff')
+  setHeader(event, 'cache-control', 'private, no-store')
+  setHeader(event, 'content-security-policy', 'sandbox')
+
+  return sendStream(event, file.stream)
+})