Add api to handle unhandled async rules exceptions

[StefanOssendorf]

A new API is added to make it possible to handle exceptions thrown by asynchronous rules.
The new interface to implement is Csla.Rules.IUnhandledAsyncRuleExceptionHandler which has two methods

• bool CanHandle(Exception, IBusinessRuleBase)

  • to decide whether this exception should be handled or not

• ValueTask Handle(Exception, IBusinessRuleBase, IRuleContext)

  • to handle the exception when CanHandle(...) == true
    With these methods you can now decide whether to handle the exception and how or let the exception be unobserved bubble up and potentially cause a crash.

You can register your implementation in two ways

• Just add the implementation to your service collection services.AddScoped<IUnhandledAsyncRuleExceptionHandler, YourImplementation>()
• Use services.AddCsla(o => o.UseUnhandledAsyncRuleExceptionHandler<YourImplementation>());. The handler is registered as scoped.

The default is still no handling of any exception thrown in an asynchronous rule.

Fixes #4725

[Copilot]

Pull Request Overview

This PR adds a new API to handle exceptions thrown by asynchronous business rules in CSLA. It introduces the IUnhandledAsyncRuleExceptionHandler interface that allows developers to decide whether to handle specific async rule exceptions and how to handle them.

Key changes:

• New interface IUnhandledAsyncRuleExceptionHandler with CanHandle and Handle methods
• Integration of exception handling into the async rule execution pipeline
• Configuration options to register custom exception handlers via dependency injection

Reviewed Changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
docs/Upgrading to CSLA 10.md	Documents the new async rule exception handling API and breaking changes
Source/Csla/Rules/IUnhandledAsyncRuleExceptionHandler.cs	Defines the new interface for handling async rule exceptions
Source/Csla/Rules/DontObserveUnhandledAsyncRuleExceptionHandler.cs	Default implementation that doesn't handle any exceptions
Source/Csla/Rules/BusinessRules.cs	Integrates exception handler into async rule execution
Source/Csla/Core/BusinessBase.cs	Updates BusinessRules instantiation to include exception handler
Source/Csla/Configuration/Fluent/CslaOptions.cs	Adds configuration option for custom exception handlers
Source/Csla/Configuration/ConfigurationExtensions.cs	Registers exception handler service in DI container
Source/tests/Csla.test/ValidationRules/TestUnhandledAsyncRuleExceptionHandler.cs	Test implementation of the exception handler interface
Source/tests/Csla.test/ValidationRules/DelayedAsynRuleExceptionRoot.cs	Test class that creates async rules with exceptions
Source/tests/Csla.test/ValidationRules/AsyncRuleTests.cs	Test cases for async rule exception handling
Source/tests/Csla.test/Csla.Tests.csproj	Adds project references for code generators

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