Function simulate_intent_with_trace 

pub async fn simulate_intent_with_trace<T>(
    catalog: &ContentCatalog,
    request: SimRequest<'_>,
    resolver: &DynDataResolver<'_>,
    progress: &dyn ProgressSink,
    trace_sink: T,
) -> Result<ChunkReport, ApplicationError>
where
    T: DecisionTraceSink + 'static,

Trace-mode entry point used by the in-browser preview pane.