Add search filter to sample pages

[wieslawsoltes]

Summary

• add a search box above the sample pages tab list
• filter tab items as the user types and show a message when nothing matches

Testing

• dotnet test AvaloniaBehaviors.sln --no-build (fails: dotnet not found)

[Copilot]

Pull Request Overview

This PR adds a search filter to the sample pages by introducing a search box above the tab list and dynamically filtering the tabs based on input.

• Added a SearchBox and a NoMatchesText control to MainView.axaml.
• Created an OnSearchTextChanged event handler in MainView.axaml.cs to filter tab items and display a message when no match is found.

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
samples/BehaviorsTestApplication/Views/MainView.axaml.cs	Introduced OnSearchTextChanged that implements dynamic tab filtering logic.
samples/BehaviorsTestApplication/Views/MainView.axaml	Modified the layout to include a search box and a message for no matches, wrapping the TabControl within a DockPanel.

Comments suppressed due to low confidence (1)

samples/BehaviorsTestApplication/Views/MainView.axaml.cs:13

• The removal of the AvaloniaXamlLoader.Load(this) call (previously in InitializeComponent) may result in UI components not being properly loaded. Verify that the view initialization occurs as expected elsewhere or reinstate the call in the constructor.

private void OnSearchTextChanged(object? sender, Avalonia.Interactivity.RoutedEventArgs e)