fix: slow start of jellyfin

Jellyfin.Plugin.SmartNotify/Notifiers/SmartNotifyBackgroundService.cs

@@ -50,11 +50,7 @@ public class SmartNotifyBackgroundService : IHostedService, IDisposable
     {
         _logger.LogInformation("SmartNotify background service starting");
 
-        // Pre-populate DB with all existing library items so they're recognized as "known".
-        // This prevents mass notifications on first run or after DB reset.
-        SeedExistingLibraryItems();
-
-        // Subscribe to library events
+        // Subscribe to library events (before seeding so we don't miss items added during seed).
         _libraryManager.ItemAdded += OnItemAdded;
         _libraryManager.ItemRemoved += OnItemRemoved;
 
@@ -64,6 +60,10 @@ public class SmartNotifyBackgroundService : IHostedService, IDisposable
         _processTimer.AutoReset = true;
         _processTimer.Start();
 
+        // Pre-populate DB with existing library items in the background
+        // so we don't block Jellyfin startup.
+        _ = Task.Run(() => SeedExistingLibraryItems(), cancellationToken);
+
         _logger.LogInformation("SmartNotify is now monitoring library changes");
 
         return Task.CompletedTask;