Fix: transient disposable detection misses IAsyncDisposable-only services

[Copilot]

• Fix PatchForDetectIncorrectUsageOfTransientDisposables to check IAsyncDisposable in open generic check
• Fix PatchForDetectIncorrectUsageOfTransientDisposables switch case for type-based descriptors to check IAsyncDisposable
• Fix CreatePatchedFactoryDescriptor to detect IAsyncDisposable at runtime
• Fix CreatePatchedKeyedFactoryDescriptor to detect IAsyncDisposable at runtime
• Add private IsDisposableType helper to avoid repetition
• Add TransientAsyncDisposable, AsyncDisposableConsumer, AsyncDisposableConsumerFactory test fixtures
• Add test: resolving IAsyncDisposable-only transient from root scope with validation throws
• Add test: resolving IAsyncDisposable-only transient from a child scope with validation does not throw (with GetDisposables assertions)
• Add test: factory-registered IAsyncDisposable-only service from root scope with validation throws
• Add test: factory-registered IAsyncDisposable-only service from child scope does not throw (with GetDisposables assertions)
• Add test: keyed IAsyncDisposable-only transient from root scope with validation throws
• Add test: keyed factory IAsyncDisposable-only service from root scope with validation throws
• All 30 transient disposable tests pass on net8.0, net9.0, net10.0

Original prompt

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This section details on the original issue you should resolve

<issue_title>Bug: Transient disposable detection misses IAsyncDisposable-only services</issue_title>
<issue_description>## Description

In DetectIncorrectUsageOfTransientDisposables.cs, the transient disposable detection only checks for typeof(IDisposable).IsAssignableFrom(...). Services that implement only IAsyncDisposable (without IDisposable) will leak from the root scope undetected.

Example

// Current code only checks IDisposable:
if (typeof(IDisposable).IsAssignableFrom(descriptor.ImplementationType))

// But a service like this would be missed:
public class MyAsyncService : IAsyncDisposable
{
    public ValueTask DisposeAsync() { /* cleanup */ }
}

Impact

Services implementing only IAsyncDisposable that are registered as transient will not trigger the diagnostic exception when resolved from the root scope, potentially causing memory leaks — the exact scenario this detection feature is designed to prevent.

Suggested Fix

Check both interfaces:

typeof(IDisposable).IsAssignableFrom(type) || typeof(IAsyncDisposable).IsAssignableFrom(type)

This applies to multiple locations in PatchForDetectIncorrectUsageOfTransientDisposables and related patching methods.</issue_description>

<agent_instructions>write tests to confirm the issue and the resolution</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Bug: Transient disposable detection misses IAsyncDisposable-only services #21

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[Copilot]

Pull request overview

This pull request fixes a bug in the transient disposable detection feature where services implementing only IAsyncDisposable (without IDisposable) were not detected, potentially causing memory leaks when resolved from the root scope.

Changes:

• Introduced IsDisposableType helper method that checks both IDisposable and IAsyncDisposable interfaces
• Updated all registration-time type checks to use the new helper method
• Updated all runtime checks in factory descriptors to detect both disposal interfaces
• Added comprehensive test coverage for IAsyncDisposable-only services including type-based, factory-based, and keyed service scenarios

Reviewed changes

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

File	Description
src/Mammoth.Extensions.DependencyInjection/DetectIncorrectUsageOfTransientDisposables.cs	Added IsDisposableType helper and updated all disposable type checks to cover both IDisposable and IAsyncDisposable
src/Mammoth.Extensions.DependencyInjection.Tests/DetectIncorrectUsageOfTransientDisposablesTests.cs	Added test fixtures and six test methods covering type-based, factory-based, and keyed scenarios for IAsyncDisposable-only services

[AGiorgetti]

@copilot apply changes based on the comments in this thread