Function classify_json_text 

pub fn classify_json_text(text: &str) -> JsonClass

Classify a JSON document: a .pio.json package, or a case document across the transmission and distribution domains.

A package is recognized by a top level model_kind of "balanced" or "multiconductor" plus a model key; the value check keeps a case document that happens to carry those key names from being misrouted. For a case, Unknown means there is no recognized top level marker, and Ambiguous means the document contains strong markers from both domains, so the caller must ask the user for an explicit format.