CXone Studio Snippet: Parsing nested JSON from REST Proxy response

I’m trying to map a nested JSON response from a CXone Studio REST Proxy call. The endpoint returns {'data': [{'id': 123}]}, but my ASSIGN action fails to extract the ID. Here’s the snippet:

GetRESTProxy('myProxy')
ASSIGN('result', result.GetRESTProxy('myProxy').response)

The result variable just shows [object Object]. I need to get result.data[0].id into a flow variable. How do I traverse this array in Studio scripting?