Rewrite guest confirmation text; add discount and multi-day checkout

Copy button text now matches the exact guest-facing template
requested — "Ваше бронирование подтверждено!", Гость/Номер для
связи/Объект бронирования/Количество гостей/Дополнительные
пожелания/Скидка — dropping the internal-only fields (source, who
booked it) since this text gets pasted straight to the client, not
kept for internal records (those still show on the on-screen summary
card).

New checkOutDate column (nullable — null means same-day, the common
case) lets a booking span multiple days; the Google Calendar link and
copy text both show the date range when set. New discount column
(same shape as prepayment) feeds the new "Скидка" line.

Statistics page gains a money row for the selected month: total
booked, prepayments collected, amount still outstanding, and total
discount given.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Gh2UXUQUVBWroWEnn1FLFG

src/lib/bookings/format.ts

@@ -4,11 +4,13 @@ export interface BookingSummaryInput {
   phone: string;
   objectNames: string[];
   date: Date;
+  checkOutDate: Date | null;
   checkIn: string;
   checkOut: string;
   guestCount: number;
   cost: number;
   prepayment: number;
+  discount: number;
   comment: string | null;
   source: string | null;
   bookedByName: string;
@@ -21,24 +23,26 @@ function formatDate(d: Date): string {
 }
 
 /**
- * Plain-text booking summary — deliberately mirrors the old Telegram bot's
- * "Готово! Вот что я забронировал:" message format so staff can paste it
- * anywhere they're used to pasting the bot's output.
+ * Guest-facing confirmation text for the "Скопировать бронирование" button
+ * — meant to be pasted straight to the client (WhatsApp/Telegram/SMS), so
+ * it deliberately excludes internal-only fields (source, who booked it).
+ * Field set and order match exactly what was asked for; a multi-day stay's
+ * date line shows both days ("дд.мм.гггг - дд.мм.гггг").
  */
 export function formatBookingSummary(b: BookingSummaryInput): string {
+  const dateLine = b.checkOutDate ? `${formatDate(b.date)} - ${formatDate(b.checkOutDate)}` : formatDate(b.date);
   const lines = [
-    `Номер бронирования: ${b.bookingNumber}`,
-    `Контактное лицо: ${b.contactName}`,
-    b.phone,
-    `Объект: ${b.objectNames.join("/") || "—"}`,
-    `Дата: ${formatDate(b.date)}`,
+    `Ваше бронирование подтверждено! Номер бронирования: ${b.bookingNumber}`,
+    `Гость: ${b.contactName}`,
+    `Номер для связи: ${b.phone}`,
+    `Объект бронирования: ${b.objectNames.join("/") || "—"}`,
+    `Дата: ${dateLine}`,
     `Время заезда/выезда: ${b.checkIn} - ${b.checkOut}`,
-    `Количество людей: ${b.guestCount}`,
+    `Количество гостей: ${b.guestCount}`,
     `Стоимость бронирования: ${b.cost}`,
     `Предоплата: ${b.prepayment}`,
-    `Комментарий: ${b.comment?.trim() || "-"}`,
-    `Откуда пришли: ${b.source?.trim() || "-"}`,
-    `Кто забронировал: ${b.bookedByName}`,
+    `Дополнительные пожелания: ${b.comment?.trim() || "-"}`,
+    `Скидка: ${b.discount}`,
   ];
   return lines.join("\n");
 }