Improve ButtonPopup accessibility and code formatting

Refactored the `VerticalStackLayout.Resources` section in
`ButtonPopup.xaml` for better readability and consistency.

Added a `Loaded` event handler (`Label_Loaded`) to the `Label`
with the `Title` style to set semantic focus on load, enhancing
accessibility. Implemented the `Label_Loaded` method in
`ButtonPopup.xaml.cs` to handle this functionality.

Author: IeuanWalker

samples/CommunityToolkit.Maui.Sample/Views/Popups/ButtonPopup.xaml

@@ -6,37 +6,37 @@
 	xmlns:mct="http://schemas.microsoft.com/dotnet/2022/maui/toolkit"
     BackgroundColor="LightCoral">
 
-	<VerticalStackLayout Spacing="6">
-		<VerticalStackLayout.Resources>
-			<ResourceDictionary>
-				<Style x:Key="Title" TargetType="Label">
-					<Setter Property="FontSize" Value="26" />
-					<Setter Property="FontAttributes" Value="Bold" />
-					<Setter Property="TextColor" Value="#000" />
-					<Setter Property="VerticalTextAlignment" Value="Center" />
-					<Setter Property="HorizontalTextAlignment" Value="Center" />
-				</Style>
-				<Style x:Key="Divider" TargetType="BoxView">
-					<Setter Property="HeightRequest" Value="1" />
-					<Setter Property="Margin" Value="50, 12" />
-					<Setter Property="Color" Value="#c3c3c3" />
-				</Style>
-				<Style x:Key="Content" TargetType="Label">
-					<Setter Property="HorizontalTextAlignment" Value="Start" />
-					<Setter Property="VerticalTextAlignment" Value="Center" />
-				</Style>
-				<Style x:Key="ConfirmButton" TargetType="Button">
-					<Setter Property="VerticalOptions" Value="End" />
-				</Style>
-			</ResourceDictionary>
-		</VerticalStackLayout.Resources>
+    <VerticalStackLayout Spacing="6">
+        <VerticalStackLayout.Resources>
+            <ResourceDictionary>
+                <Style x:Key="Title" TargetType="Label">
+                    <Setter Property="FontSize" Value="26" />
+                    <Setter Property="FontAttributes" Value="Bold" />
+                    <Setter Property="TextColor" Value="#000" />
+                    <Setter Property="VerticalTextAlignment" Value="Center" />
+                    <Setter Property="HorizontalTextAlignment" Value="Center" />
+                </Style>
+                <Style x:Key="Divider" TargetType="BoxView">
+                    <Setter Property="HeightRequest" Value="1" />
+                    <Setter Property="Margin" Value="50, 12" />
+                    <Setter Property="Color" Value="#c3c3c3" />
+                </Style>
+                <Style x:Key="Content" TargetType="Label">
+                    <Setter Property="HorizontalTextAlignment" Value="Start" />
+                    <Setter Property="VerticalTextAlignment" Value="Center" />
+                </Style>
+                <Style x:Key="ConfirmButton" TargetType="Button">
+                    <Setter Property="VerticalOptions" Value="End" />
+                </Style>
+            </ResourceDictionary>
+        </VerticalStackLayout.Resources>
 
-		<Label Style="{StaticResource Title}" Text="Button Popup" />
-		<BoxView Style="{StaticResource Divider}" />
-		<Label Style="{StaticResource Content}" Text="This is a platform specific popup with a .NET MAUI View being rendered. The behaviors of the popup will confirm to 100% this platform look and feel, but still allows you to use your .NET MAUI controls." />
-		<Button
+        <Label Style="{StaticResource Title}" Text="Button Popup" Loaded="Label_Loaded" />
+        <BoxView Style="{StaticResource Divider}" />
+        <Label Style="{StaticResource Content}" Text="This is a platform specific popup with a .NET MAUI View being rendered. The behaviors of the popup will confirm to 100% this platform look and feel, but still allows you to use your .NET MAUI controls." />
+        <Button
 			Clicked="Button_Clicked"
 			Style="{StaticResource ConfirmButton}"
 			Text="OKAY" />
-	</VerticalStackLayout>
+    </VerticalStackLayout>
 </mct:Popup>

samples/CommunityToolkit.Maui.Sample/Views/Popups/ButtonPopup.xaml.cs

@@ -11,4 +11,12 @@ void Button_Clicked(object? sender, EventArgs e)
 	{
 		CloseAsync();
 	}
+
+	void Label_Loaded(object sender, EventArgs e)
+	{
+		if (sender is Label label)
+		{
+			label.SetSemanticFocus();
+		}
+	}
 }