ToolConstraint Type Cannot Be Identified or Unboxed After API Call

[sandrohanea]

Confirm this is a feature request for the .NET library and not the underlying OpenAI API

• This is a feature request for the .NET library

Describe the feature or improvement you are requesting

When creating an Assistant Run for a specific thread a tool constraint can be defined: auto, none or required.

However, when the run is retrieved, it is impossible to tell which type was deserialized as the instance contains no public properties and ToString() is not writing something special.

I tried to compare it with the static options (e.g. ToolConstraint.Auto) but the result is false, and no property is exposed to identify that specific tool constraint.

Here is some code sample:

var assistantsClient = new AssistantsClient("someApiKey");

var runResponse = await assistantsClient.GetRunAsync("thread_gA...kv2", "run_ecofR9n2oxKh...dWjM");

if (runResponse.Value.ToolConstraint == ToolConstraint.Auto)
{
    Console.WriteLine("ToolConstraint is Auto");
}
else if(runResponse.Value.ToolConstraint == ToolConstraint.None)
{
    Console.WriteLine("ToolConstraint is None");
}
else if (runResponse.Value.ToolConstraint == ToolConstraint.Required)
{
    Console.WriteLine("ToolConstraint is Required");
}
else
{
    Console.WriteLine("ToolConstraint is Unknown");
}

Console.WriteLine(runResponse.Value.ToolConstraint);

The above code will display

ToolConstraint is Unknown
OpenAI.Assistants.ToolConstraint
``

There is no way to unbox that information as type is private.

### Additional context

Same behavior is observed for other enum-like types: (e.g. `FileChunkingStrategy`)