Function extract_diagnostics 

pub fn extract_diagnostics(
    json_str: &str,
    model: &SemanticModel,
    out: &mut Vec<Diagnostic>,
    source_override: Option<&RuleOrigin>,
) -> Result<(), String>

Parses a JSON array of rule outputs, appending a Diagnostic for each element. The array iteration and per-element parsing live in [extract_diagnostics_from_value]; this entry point only turns the string into a value first.