fix: BookingConfirmPage date format + guest confirmation email on payment

- Fix date display: slice ISO timestamp to first 10 chars before splitting
- Add sendBookingConfirmedEmail() to email.ts — sends green styled HTML email
  with booking details (dates, amount) on payment.succeeded webhook
- Webhook now sends confirmation email to guest email if present

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

backend/src/routes/yookassaWebhook.ts

@@ -1,6 +1,7 @@
 import { FastifyPluginAsync } from 'fastify'
 import { db } from '../db'
 import { broadcast } from './ws'
+import { sendBookingConfirmedEmail } from '../email'
 
 const yookassaWebhookRoutes: FastifyPluginAsync = async (fastify) => {
   // POST /api/yookassa/webhook
@@ -19,8 +20,11 @@ const yookassaWebhookRoutes: FastifyPluginAsync = async (fastify) => {
       const { rows } = await db.query<{
         id: string; hotel_id: string; booking_id: string | null
         total_amount: string; slug: string
+        guest_name: string; guest_email: string | null
+        check_in: string; check_out: string; hotel_name: string
       }>(
-        `SELECT ob.id, ob.hotel_id, ob.booking_id, ob.total_amount, h.slug
+        `SELECT ob.id, ob.hotel_id, ob.booking_id, ob.total_amount, h.slug,
+                ob.guest_name, ob.guest_email, ob.check_in, ob.check_out, h.name AS hotel_name
            FROM online_bookings ob
            JOIN hotels h ON h.id = ob.hotel_id
           WHERE ob.yookassa_payment_id = $1
@@ -50,6 +54,18 @@ const yookassaWebhookRoutes: FastifyPluginAsync = async (fastify) => {
             broadcast(ob.slug, { type: 'booking:updated', booking: bRows[0] })
           }
         }
+        // Send confirmation email to guest
+        if (ob.guest_email) {
+          sendBookingConfirmedEmail({
+            to: ob.guest_email,
+            guestName: ob.guest_name,
+            hotelName: ob.hotel_name,
+            checkIn: ob.check_in,
+            checkOut: ob.check_out,
+            totalAmount: ob.total_amount,
+            bookingConfirmUrl: `https://app.hotelsync.ru/booking-confirm/${ob.id}`,
+          }).catch(() => {}) // don't fail webhook on email error
+        }
       } else if (event === 'payment.canceled') {
         await db.query(
           `UPDATE online_bookings SET status = 'cancelled', yookassa_status = 'canceled' WHERE id = $1`,