Make HybridWebViewHandler throw JS exceptions in C# by default

[mattleibow]

Description of Change

We could not make exceptions by default in .NET 9 as that would be breaking, but it really is the most sensible.

If there is an exception in .NET 9, then the method never returns.

[Copilot]

PR Overview

This PR updates the logic for determining whether HybridWebViewHandler should throw JavaScript exceptions in C# by default, aligning with the intended behavior for upcoming .NET releases.

• Inverts the default behavior by returning true when the AppContext switch is not set.
• Updates the expression to ensure exceptions are thrown by default in .NET 10 while preserving the ability to override.

Reviewed Changes

File	Description
src/Core/src/Handlers/HybridWebView/HybridWebViewHandler.cs	Inverts the default value for throwing JS exceptions to true, updating the logic accordingly.

Copilot reviewed 1 out of 1 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (1)

src/Core/src/Handlers/HybridWebView/HybridWebViewHandler.cs:98

• The updated logic inverts the default behavior so that exceptions are thrown by default when the switch is not set. Update the accompanying comment (currently mentioning .NET 10) to clearly describe the new default behavior, and ensure that relevant test cases in TestCases.HostApp and TestCases.Shared.Tests are added to validate this behavior.

private static bool IsInvokeJavaScriptThrowsExceptionsEnabled =>
			!AppContext.TryGetSwitch(InvokeJavaScriptThrowsExceptionsSwitch, out var enabled) || enabled;

[Copilot]

PR Overview

This PR updates the HybridWebViewHandler to throw JavaScript exceptions in C# by default, while also updating the test configuration to remove redundant explicit switch settings.

• Changed the default behavior in HybridWebViewHandler.cs to enable JS exception throwing by default.
• Removed explicit switch setting from MauiProgram.cs in DeviceTests.

Reviewed Changes

File	Description
src/Core/src/Handlers/HybridWebView/HybridWebViewHandler.cs	Updated logic to default to throwing JS exceptions.
src/Controls/tests/DeviceTests/MauiProgram.cs	Removed explicit AppContext switch setting for tests.

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

Comments suppressed due to low confidence (1)

src/Core/src/Handlers/HybridWebView/HybridWebViewHandler.cs:97

• The TODO comment is now outdated since the default behavior has been updated to throw JS exceptions. Please update or remove the comment to reflect the current implementation.

// TODO: .NET 10 flip the default to true for .NET 10