Function build_job_traced 

pub fn build_job_traced<D>(
    resource_key: &str,
    operation: &str,
    overwrite_policy: OverwritePolicy,
    items: Vec<(String, D, SizeBucket)>,
    trace_ctx: TraceCtx,
) -> BatchJob<D>
where
    D: Clone + Send + Sync + Serialize,

Helper to build a BatchJob with trace context propagation.

Each item receives the provided trace_ctx and a freshly generated AttemptId (one per item, since each item is its own retry-owner boundary within the batch). TrialId is left None — it will be stamped by the executor on each concrete execution.