Maintenance mode activates after current draw completes

- When admin enables maintenance, it's set to 'pending' state
- Maintenance activates automatically after the current draw completes
- Admin can use immediate=true to force immediate activation
- Frontend shows 'Maintenance Scheduled' banner when pending
- Telegram bot warns users but still allows purchases when pending
- Both mode and pending status tracked in system_settings table

telegram_bot/src/handlers/buy.ts

@@ -33,6 +33,26 @@ export async function handleBuyCommand(
   logUserAction(userId, 'Initiated ticket purchase');
 
   try {
+    // Check maintenance mode first
+    const maintenance = await apiClient.checkMaintenanceStatus();
+    if (maintenance.enabled) {
+      await bot.sendMessage(
+        chatId, 
+        messages.errors.maintenance(maintenance.message || 'System is under maintenance.'),
+        { parse_mode: 'Markdown' }
+      );
+      return;
+    }
+
+    // Warn if maintenance is pending (but still allow purchase)
+    if (maintenance.pending) {
+      await bot.sendMessage(
+        chatId,
+        messages.errors.maintenancePending,
+        { parse_mode: 'Markdown' }
+      );
+    }
+
     const user = await stateManager.getUser(userId);
 
     if (!user) {