Adding support for Tray context menus

[dotMorten]

        var m = WindowManager.Get(this);
        m.IsVisibleInTray = true;
        m.TrayIconInvoked += TrayIconClicked;
    
   ///...

    private void TrayIconClicked(object? sender, TrayIconInvokedEventArgs e)
    {
        if (e.Type == TrayIconInvokeType.RightMouseUp)
        {
            var flyout = new MenuFlyout();
            flyout.Items.Add(new MenuFlyoutItem() { Text = "WinUI Context Menus!", IsEnabled = false });
            flyout.Items.Add(new MenuFlyoutItem() { Text = "Try Left clicking", IsEnabled = false });
            flyout.Items.Add(new MenuFlyoutSeparator());
            flyout.Items.Add(new MenuFlyoutItem() { Text = "Exit WinUIEx" });
            ((MenuFlyoutItem)flyout.Items.Last()).Click += (s, e) => this.Close();
            e.Flyout = flyout; // Set a flyout to present. Can be any FlyoutBase kind
        }
        else if (e.Type == TrayIconInvokeType.LeftMouseDown)
        {
            var flyout = new Flyout();
            flyout.SystemBackdrop = new MicaBackdrop();
            StackPanel stackPanel = new StackPanel();
            stackPanel.Children.Add(new TextBlock() { Text = "You can put any content here!", FontWeight = Microsoft.UI.Text.FontWeights.Bold });
            stackPanel.Children.Add(new TextBlock() { Text = "Now try right-clicking the icon" });
            flyout.Content = stackPanel;
            e.Flyout = flyout; 
        }
    }

[Copilot]

Pull Request Overview

This PR adds comprehensive support for tray context menus and flyouts to the WinUIEx library. It enables developers to display WinUI 3 flyouts when users interact with the system tray icon through various mouse actions.

Key changes:

• Refactored tray icon functionality into a separate partial class for better organization
• Added comprehensive event handling for all tray icon mouse interactions (left/right clicks, double-clicks, mouse up/down)
• Implemented support for displaying WinUI 3 flyouts anchored to the tray icon location

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
src/WinUIExSample/MainWindow.xaml.cs	Added example implementation showing both MenuFlyout and custom Flyout usage with tray icon events
src/WinUIEx/WindowManager.cs	Refactored tray icon message handling to use new ProcessTrayIconEvents method and moved tray functionality to partial class
src/WinUIEx/WindowManager.TrayIcon.cs	New partial class containing all tray icon functionality, event handling, and flyout display logic
src/WinUIEx/WinUIEx.csproj	Updated package release notes to describe the new tray flyout feature
src/Directory.Build.targets	Updated version from 2.8.0 to 2.9.0 and baseline validation version

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[Copilot]

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[Copilot]

Pull Request Overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 3 comments.

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[Copilot]

Pull Request Overview

Copilot reviewed 8 out of 8 changed files in this pull request and generated 3 comments.

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}