Make in memory assemblies in InteractiveAssemblyLoader can be collected when use scripting

[zh6335901]

See #31751 and #41722

Add isCollectible parameter to InteractiveAssemblyLoader makes collecting assemblies that in memory possible.

My test code:

while (true)
{
    var loader = new InteractiveAssemblyLoader(isCollectible: true);
    var options = ScriptOptions.Default
        .AddReferences(MetadataReference.CreateFromFile(typeof(TestClass).Assembly.Location))
        .WithImports("System", "ScriptingClassLibrary");

    var script = CSharpScript.Create("new TestClass().ToJson(1)", options, assemblyLoader: loader);
    var result = await script.RunAsync().ConfigureAwait(false);
    result = await result.ContinueWithAsync("1 + 2").ConfigureAwait(false);
    result = await result.ContinueWithAsync("new TestClass().ToJson(\"aaa\")").ConfigureAwait(false);
    result = await result.ContinueWithAsync("new TestClass().ToJson(false)").ConfigureAwait(false);
    result = await result.ContinueWithAsync("1 + 3").ConfigureAwait(false);

    loader.Dispose();

    GC.Collect();
    GC.WaitForPendingFinalizers();

    await Task.Delay(100).ConfigureAwait(false);

    var currentProcess = Process.GetCurrentProcess();
    Console.WriteLine($"Process handle count: {currentProcess.HandleCount}");
}

Test result:

You can see memory usage and process handle count is steady.

But same test code(without isCollectible parameter) use Microsoft.CodeAnalysis.CSharp.Scripting 4.12.0-1.final package:

[zh6335901]

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[zh6335901]

I didn't find any place to invoke this Dispose method in roslyn repo, I don't sure it's safe or suitable to clear _loadedAssembliesBySimpleName , But in my test case i don't see any negative behavior

[zh6335901]

Anyone can review it?

[DraconInteractive]

Curious to whether this is still applicable? Running into the problem of assemblies hanging around in memory on the latest branch of ros, this seems like a solid solution to me. Hope it gets bumped for review!

[meetsekhar]

Could you please let me know if this fix is working and is available? We’re experiencing a production issue.