Function build_dataplane_span 

pub fn build_dataplane_span(
    trace_context: TraceContext,
    kind: DataplaneSpanKind,
    operation: &str,
    outcome: &str,
    resource_kind: ResourceKind,
    lease_id: Option<u128>,
    start_time_unix_us: u64,
    end_time_unix_us: u64,
) -> ResourceSpan

Build a data-plane span using the Phase 219 canonical span names. The helper keeps the lease id in the span body (never a Prometheus label) and routes resource kind / operation / outcome through stable attribute keys so consumers see the same shape across families.