feat(producer,cli): full telemetry visibility for DE parallel-router/inversion failures

render_error previously carried zero DE-cohort context — a hard failure while
routed (worker crash, OOM, capture timeout from the fixed 3-worker pin
overriding calibration) was indistinguishable from any other failure. The
data existed (RenderCaptureObservability is mutated live and survives into
job.errorDetails on the failure path) but was never projected into the
render_error payload, which only ever drew de_* fields from perfSummary
(success-only).

- RenderCaptureObservability now also records dePreInversionWorkers /
  dePreRouterWorkers — the worker count calibration would have picked absent
  the experiment — so a resource-pressure failure can be correlated with the
  router overriding a lower calibrated count.
- New capture-sourced de_* fields on RenderObservabilityTelemetryPayload,
  shared by trackRenderComplete and trackRenderError. Explicit
  perfSummary-sourced fields still win on render_complete (spread moved
  first in the event object) — this is purely a failure-path fallback.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

packages/producer/src/services/render/observability.ts

@@ -44,8 +44,12 @@ export interface RenderCaptureObservability {
   deSelfVerifyFallback?: boolean;
   /** Auto-parallel inversion outcome: "inverted" (fired, held) | "reverted" (fired, self-verify retry rolled back). */
   deWorkerInversion?: "inverted" | "reverted";
+  /** Worker count the resolver would have used absent the inversion; undefined if it never fired. */
+  dePreInversionWorkers?: number;
   /** DE parallel-router outcome: "routed" (fired, held) | "reverted" (fired, self-verify retry rolled back). */
   deParallelRouter?: "routed" | "reverted";
+  /** Worker count the resolver would have used absent the router; undefined if it never fired. */
+  dePreRouterWorkers?: number;
   protocolTimeoutMs?: number;
   pageNavigationTimeoutMs?: number;
   playerReadyTimeoutMs?: number;

packages/producer/src/services/renderOrchestrator.ts

@@ -1970,7 +1970,18 @@ export async function executeRenderJob(
       );
       workerCount = 1;
     }
-    updateCaptureObservability({ workerCount, deWorkerInversion, deParallelRouter });
+    updateCaptureObservability({
+      workerCount,
+      deWorkerInversion,
+      deParallelRouter,
+      // Recorded here (not just in the success-path perfSummary) so a hard
+      // failure while routed/inverted still tells us what worker count the
+      // resolver would have used absent the experiment — the DE-router pin
+      // to 3 workers regardless of calibration is the leading suspect for
+      // any resource-pressure failure unique to this cohort.
+      dePreInversionWorkers: deWorkerInversion ? preRoutingWorkerCount : undefined,
+      dePreRouterWorkers: deParallelRouter ? preRoutingWorkerCount : undefined,
+    });
     observability.checkpoint("worker_resolution", "resolved", {
       workerCount,
       deWorkerInversion: deWorkerInversion ?? "none",