Major UX improvements across multiple pages

Шахматка:
- Date/period picker dropdown on navigation button (choose start date + days window)
- Cancelled bookings fade out with animation after 1 second

Бронирования:
- Clickable column headers with sort asc/desc (Гость, Заезд, Выезд, Статус, Источник, Сумма)

Страница входа:
- Removed role-based account selector — just email + password
- System auto-detects role/hotel from credentials

Настройки:
- New "Бронирование" section with room assignment strategy (spread/together/sequential/manual)
- Notifications: SMTP email config + SMS provider config (SMSC, SMS.ru, МТС, etc.)

Модули:
- Added Housekeeping and Channel Manager as proper modules
- Channel Manager lists: Booking.com, Airbnb, Яндекс Путешествия, Островок, Суточно.ру, OneTwoTrip
- Housekeeping visible to all roles (including housekeeper) via module status
- Sidebar now uses module status to show/hide Уборка and Каналы

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

backend/src/server.ts

@@ -0,0 +1,38 @@
+import { db } from './db'
+import { redis } from './redis'
+import { runMigrations } from './migrate'
+import { seedIfEmpty } from './seed'
+import { buildApp } from './app'
+import { config } from './config'
+
+async function waitForDb(retries = 10, delayMs = 3000) {
+  for (let i = 1; i <= retries; i++) {
+    try {
+      await db.query('SELECT 1')
+      console.log('[db] Connected')
+      return
+    } catch {
+      console.log(`[db] Not ready, retry ${i}/${retries}...`)
+      await new Promise(r => setTimeout(r, delayMs))
+    }
+  }
+  throw new Error('Database not available after retries')
+}
+
+async function main() {
+  await waitForDb()
+  await runMigrations()
+  await seedIfEmpty()
+
+  await redis.connect()
+  console.log('[redis] Connected')
+
+  const app = await buildApp()
+  await app.listen({ port: config.port, host: '0.0.0.0' })
+  console.log(`[server] Listening on :${config.port}`)
+}
+
+main().catch(err => {
+  console.error('[server] Fatal error:', err)
+  process.exit(1)
+})