docs(MA0042): Document false positive when calling sync method from its own async counterpart

[Copilot]

MA0042 incorrectly fires when a sync method is called from within the async method it would suggest as a replacement. Applying the fix in this case causes infinite recursion.

Changes

• docs/Rules/MA0042.md: Added a "Known limitations" section documenting the false positive scenario with a code example and instructions to suppress the diagnostic manually (#pragma warning disable MA0042 or [SuppressMessage]).

public sealed class Sample
{
    public void Run() { }

    public async Task RunAsync()
    {
        // MA0042 fires here suggesting RunAsync — but that would be infinite recursion.
        // Suppress manually: #pragma warning disable MA0042
        Run();
    }
}

The analyzer cannot detect this case automatically, so manual suppression is required.

Original prompt

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This section details on the original issue you should resolve

<issue_title>MA0042 is reported when the async method it proposed to use is the method from within the invocation is done</issue_title>
<issue_description>### Version of the Meziantou.Analyzer NuGet package

3.0.11

Rule Identifier

MA0042

Target Framework

.NET 10.0

C# Language version

C# 14

Description

MA0042 is currently "wrongfully" reported for a non-async method call when that call is done from within the async method it proposed to use. Applying the "suggestion" would lead to a stackoverflow.

I came across this in legacy code.

Reproduction Steps

Minimal code:

public sealed class B
{
    public void Run()
    {
    }

    public async Task RunAsync()
    {
        Run(); // MA0042: Use 'RunAsync' instead of 'Run' | NOK, should not be reported
    }

    public async Task Work()
    {
    }

    public async Task WorkAsync()
    {
        Run(); // MA0042: Use 'RunAsync' instead of 'Run' | OK
    }
}

Other information

No response</issue_description>

<agent_instructions>Can you update the rule documentation to indicate that the rule must be disabled manually for specific cases</agent_instructions>

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

@meziantou Duplicate of #788. Will improve the documentation

• Fixes MA0042 is reported when the async method it proposed to use is the method from within the invocation is done #1034

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