Bug: Top-level array always transforms into empty array

```csx
#r "nuget: JUST.net, 4.4.1"
using JUST;
Console.WriteLine(new JsonTransformer(new()).Transform("{arr:[1,2,3]}", ""));
Console.WriteLine(new JsonTransformer(new()).Transform("[1,2,3]", ""));
```
```stdout
{"arr":[1,2,3]}
[]
```