fix(render): node reports progress → moving bar + ETA (was stuck 0%/Preparing)

The node's onProgress callback only LOGGED — it never POSTed, so render_progress stayed
0 and step stayed Preparing (no bar, no ETA). Add render-svc POST
/v1/internal/render/jobs/{id}/progress (UpdateJobProgress: set render_progress + bump
step Queued/Preparing→Rendering once >0) + client UpdateProgress + wire onProgress to
post it (8s best-effort timeout, AE-CPU/DB-starvation tolerant). Preview already posts;
real-frame preview is epic C.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

services/node-agent/cmd/agent/main.go

@@ -445,6 +445,13 @@ func (a *Agent) runJob(ctx context.Context, job *client.ClaimedJob) {
 
 	onProgress := func(ctx context.Context, pct int, msg string) error {
 		log.Printf("[job %s] %d%% %s", job.JobID, pct, msg)
+		// Report to the orchestrator so the UI shows a moving bar + ETA (best-effort,
+		// short timeout — AE pegs CPU so the DB may be slow on a single-box dev setup).
+		pCtx, cancel := context.WithTimeout(ctx, 8*time.Second)
+		defer cancel()
+		if err := a.orch.UpdateProgress(pCtx, job.JobID, pct); err != nil {
+			log.Printf("[job %s] progress push error: %v", job.JobID, err)
+		}
 		return nil
 	}