[C# APIView] Explicit interface implementation is rendered as a member of AzureAISearchIndex

The C# parser is misrendering this explicit interface implementation in APIView.

Bad code snippet:
```csharp
void IJsonModel.Write(Utf8JsonWriter writer, ModelReaderWriterOptions options);
```

What it should do:
- Treat this as an explicit interface implementation on `IJsonModel`.
- Do not render it as if `AzureAISearchIndex` itself contains a method named `Write`.
- The containing type/member association in APIView should be corrected by the parser.

Good code snippet:
```csharp
void IJsonModel.Write(Utf8JsonWriter writer, ModelReaderWriterOptions options)
{
// implementation
}
```

Start with the C# parser used by APIView and reproduce the bad snippet from the issue. Verify that the explicit interface implementation is associated with IJsonModel rather than AzureAISearchIndex, then confirm the corrected rendering with the good snippet.

Written by the indexing model from the issue text.