Update .NET

[alex-oswald]

• Update to .NET 9
• Remove support for .NET 6 and .NET 7
• Updated the sample app to show how you might perform task in the background, while sending events to the UI thread

[Copilot]

Copilot reviewed 5 out of 16 changed files in this pull request and generated 2 comments.

Files not reviewed (11)

• samples/AppContext/AppContext.csproj: Language not supported
• samples/BlazorHybrid/BlazorHybrid.csproj: Language not supported
• samples/SampleApp/Form1.Designer.cs: Language not supported
• samples/SampleApp/Form1.resx: Language not supported
• samples/SampleApp/SampleApp.csproj: Language not supported
• src/WindowsFormsLifetime/WindowsFormsLifetime.csproj: Language not supported
• tests/WindowsFormsLifetime.Tests/WindowsFormsLifetimeTests.csproj: Language not supported
• tests/WindowsFormsLifetime.Tests/FormProviderTests.cs: Evaluated as low risk
• src/WindowsFormsLifetime/HostBuilderExtensions.cs: Evaluated as low risk
• samples/SampleApp/FormSpawnHostedService.cs: Evaluated as low risk
• TestWindowsFormsLifetime.yml: Evaluated as low risk

Comments suppressed due to low confidence (3)

samples/SampleApp/TickBag.cs:14

• Add a null check for the OnTick event handler to prevent potential NullReferenceException.

OnTick?.Invoke(this, _currentTick);

samples/SampleApp/TickingHostedService.cs:21

• Ensure that the TickBag's Increment method and the OnTick event invocation are covered by tests.

await Task.Delay(2000, stoppingToken);

samples/SampleApp/Form1.cs:27

• Updating the TickLabel.Text property directly from the TickBag_OnTick method may cause cross-thread operation issues. Consider using Invoke to update the label on the UI thread.

TickLabel.Text = "Tick: {e}";