Move progress bar animation init to Loaded event

InitProgressbarAnimation is now triggered by the progress bar's Loaded event instead of during main window initialization. This ensures the animation starts only after the progress bar is fully loaded, improving reliability and preventing potential UI timing issues.

Flow.Launcher/MainWindow.xaml

@@ -342,6 +342,7 @@
                     Margin="12 0 12 0"
                     HorizontalAlignment="Center"
                     VerticalAlignment="Bottom"
+                    Loaded="ProgressBar_Loaded"
                     StrokeThickness="2"
                     Visibility="{Binding ProgressBarVisibility, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                     X1="-100"

Flow.Launcher/MainWindow.xaml.cs

@@ -199,9 +199,6 @@ namespace Flow.Launcher
                 ThemeManager.Current.ApplicationTheme = ApplicationTheme.Dark;
             }
 
-            // Initialize position
-            InitProgressbarAnimation();
-
             // Force update position
             UpdatePosition();
 
@@ -354,6 +351,11 @@ namespace Flow.Launcher
             }
         }
 
+        private void ProgressBar_Loaded(object sender, RoutedEventArgs e)
+        {
+            InitProgressbarAnimation();
+        }
+
         private async void OnClosing(object sender, CancelEventArgs e)
         {
             if (!CanClose)