[2.0.250930001-experimental1] Phi Silica GetReadyState and EnsureReadyAsync return NotReady when model is available

### Describe the bug

I'm upgrading an app from 1.8.250702007-experimental4 to WinAppSDK 2.0.250930001-experimental1. The app has some Phi SIlica functionality. Previously the following code worked:
```
auto readyState = LanguageModel::GetReadyState();
if (readyState == AIFeatureReadyState::NotReady)
{
LanguageModel::EnsureReadyAsync().get();
}

// Create the language model and generate a response synchronously
auto languageModel = LanguageModel::CreateAsync().get();
auto responseResult = languageModel.GenerateResponseAsync(winrt::to_hstring(prompt)).get();
auto result = winrt::to_string(responseResult.Text());
```
Now, `LanguageModel::GetReadyState()` returns `AIFeatureReadyState::NotReady`. `LanguageModel::EnsureReadyAsync()` returns Status `2` indicating the operation failed. However, if I remove the ready state checks and just run
```
auto languageModel = LanguageModel::CreateAsync().get();
auto responseResult = languageModel.GenerateResponseAsync(winrt::to_hstring(prompt)).get();
auto result = winrt::to_string(responseResult.Text());
return Napi::String::New(env, result);
```
The code works as expected and `result` contains the text response from Phi Silica. `LanguageModel::GetReadyState()` and `LanguageModel::EnsureReadyAsync()` appear to have a bug and claim the model isn't available/ready when it is.

### Steps to reproduce the bug

1. Begin with a WinAppSDK 2.0.250930001-experimental1 app with configuration for Phi Silica
2. Attempt to run a basic call to Phi Silica, while first checking if the model is available.

Observe: Model availability checks claim model is not available, but if you remove those checks you can still generate a LanguageModel instance and call API's.

### Expected behavior

1. Model availability checks should succeed, and model should return a generated text value.

### Screenshots

_No response_

### NuGet package version

Windows App SDK 2.0 Experimental 1: 2.0.250930001-experimental1

### Packaging type

Unpackaged, Packaged (MSIX)

### Windows version

Insider Build (xxxxx)

### IDE

Other

### Additional context

Let me know if there is a better place to file this issue instead of within this repo.

Start by reproducing the Phi Silica flow using LanguageModel::GetReadyState(), EnsureReadyAsync(), CreateAsync(), and GenerateResponseAsync() in a WinAppSDK 2.0 experimental app. Compare the readiness results with the successful generation path; done means availability checks report the model correctly and the existing text-generation call continues to work.

Written by the indexing model from the issue text.