feat: Enrich in-progress stage display and memoize pipeline page

In-progress stages now show:
- Live elapsed time (ticks every second) next to the active stage dot
- Run-level token count so far

Performance: wrapped StageTimeline, StatusFilter, WorkerStatus, and
RecentActivityFeed with React.memo. Memoized filteredVideos with useMemo.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/App.css

@@ -3689,6 +3689,22 @@ a.app-footer__repo:hover {
 .stage-timeline__step--done + .stage-timeline__step::before {
   background: #00c853;
 }
+.stage-timeline__elapsed {
+  font-size: 0.7rem;
+  font-weight: 600;
+  color: var(--color-accent);
+  margin-left: 6px;
+  font-variant-numeric: tabular-nums;
+  white-space: nowrap;
+}
+
+.stage-timeline__tokens {
+  font-size: 0.65rem;
+  color: var(--color-text-muted);
+  margin-left: 4px;
+  white-space: nowrap;
+}
+
 
 /* ── Recent Activity Feed ─────────────────────────────────────────────────── */
 

frontend/src/pages/AdminPipeline.tsx

@@ -3,7 +3,7 @@
  * expandable event log with token usage and collapsible JSON viewer.
  */
 
-import { useCallback, useEffect, useRef, useState } from "react";
+import React, { useCallback, useEffect, useMemo, useRef, useState } from "react";
 import { useSearchParams } from "react-router-dom";
 import { useDocumentTitle } from "../hooks/useDocumentTitle";
 import {
@@ -45,6 +45,19 @@ function formatTokens(n: number): string {
   return String(n);
 }
 
+
+function formatElapsed(isoStart: string | null): string {
+  if (!isoStart) return "";
+  const ms = Date.now() - new Date(isoStart).getTime();
+  if (ms < 0) return "";
+  const secs = Math.floor(ms / 1000);
+  if (secs < 60) return `${secs}s`;
+  const mins = Math.floor(secs / 60);
+  const remainSecs = secs % 60;
+  if (mins < 60) return `${mins}m ${remainSecs}s`;
+  const hrs = Math.floor(mins / 60);
+  return `${hrs}h ${mins % 60}m`;
+}
 const STATUS_LABELS: Record<string, string> = {
   not_started: "Not Started",
   queued: "Queued",
@@ -343,7 +356,7 @@ function EventLog({ videoId, status, runId }: { videoId: string; status: string;
 
 // ── Worker Status ────────────────────────────────────────────────────────────
 
-function WorkerStatus() {
+const WorkerStatus = React.memo(function WorkerStatus() {
   const [status, setStatus] = useState<WorkerStatusResponse | null>(null);
   const [error, setError] = useState<string | null>(null);
 
@@ -397,7 +410,7 @@ function WorkerStatus() {
       ))}
     </div>
   );
-}
+});
 
 // ── Debug Mode Toggle ────────────────────────────────────────────────────────
 
@@ -443,7 +456,7 @@ function DebugModeToggle({
 
 // ── Status Filter ────────────────────────────────────────────────────────────
 
-function StatusFilter({
+const StatusFilter = React.memo(function StatusFilter({
   videos,
   activeFilter,
   onFilterChange,
@@ -483,7 +496,7 @@ function StatusFilter({
       })}
     </div>
   );
-}
+});
 
 // ── Run List ─────────────────────────────────────────────────────────────────
 
@@ -614,15 +627,23 @@ const PIPELINE_STAGES = [
   { key: "stage6_embed", label: "Embed" },
 ];
 
-function StageTimeline({ video }: { video: PipelineVideoItem }) {
+const StageTimeline = React.memo(function StageTimeline({ video }: { video: PipelineVideoItem }) {
-  if (video.processing_status !== "processing" && video.processing_status !== "complete" && video.processing_status !== "error") {
+  const [, setTick] = useState(0);
+  const isProcessing = video.processing_status === "processing";
+
+  // Tick every second while processing to update elapsed time
+  useEffect(() => {
+    if (!isProcessing) return;
+    const id = setInterval(() => setTick((t) => t + 1), 1000);
+    return () => clearInterval(id);
+  }, [isProcessing]);
+
+  if (!isProcessing && video.processing_status !== "complete" && video.processing_status !== "error") {
     return null;
   }
 
   const activeStage = video.active_stage;
-  const activeStatus = video.active_stage_status; // "start" = running, "complete" = done, "error" = failed
+  const activeStatus = video.active_stage_status;
-
-  // Determine each stage's state
   const activeIdx = PIPELINE_STAGES.findIndex((s) => s.key === activeStage);
 
   return (
@@ -638,7 +659,6 @@ function StageTimeline({ video }: { video: PipelineVideoItem }) {
             else if (activeStatus === "error") stateClass = "stage-timeline__step--error";
           }
         }
-        // If video is complete, all stages are done
         if (video.processing_status === "complete") {
           stateClass = "stage-timeline__step--done";
         }
@@ -650,13 +670,19 @@ function StageTimeline({ video }: { video: PipelineVideoItem }) {
           </div>
         );
       })}
+      {isProcessing && activeStatus === "start" && (
+        <span className="stage-timeline__elapsed">{formatElapsed(video.stage_started_at)}</span>
+      )}
+      {isProcessing && video.latest_run && video.latest_run.total_tokens > 0 && (
+        <span className="stage-timeline__tokens">{formatTokens(video.latest_run.total_tokens)} tok</span>
+      )}
     </div>
   );
-}
+})
 
 // ── Recent Activity Feed ─────────────────────────────────────────────────────
 
-function RecentActivityFeed() {
+const RecentActivityFeed = React.memo(function RecentActivityFeed() {
   const [items, setItems] = useState<RecentActivityItem[]>([]);
   const [collapsed, setCollapsed] = useState(false);
   const [loading, setLoading] = useState(true);
@@ -718,7 +744,7 @@ function RecentActivityFeed() {
       )}
     </div>
   );
-}
+});
 
 // ── Main Page ────────────────────────────────────────────────────────────────
 
@@ -760,8 +786,8 @@ export default function AdminPipeline() {
   const videoRefs = useRef<Map<string, HTMLDivElement>>(new Map());
   const deepLinked = useRef(false);
 
-  // Compute filtered list (status + creator)
+  // Compute filtered list (status + creator) — memoized to avoid recomputing on unrelated state changes
-  const filteredVideos = videos.filter((v) => {
+  const filteredVideos = useMemo(() => videos.filter((v) => {
     if (activeFilter !== null && v.processing_status !== activeFilter) return false;
     if (creatorFilter !== null && v.creator_name !== creatorFilter) return false;
     if (searchQuery) {
@@ -769,7 +795,7 @@ export default function AdminPipeline() {
       if (!v.filename.toLowerCase().includes(q) && !v.creator_name.toLowerCase().includes(q)) return false;
     }
     return true;
-  });
+  }), [videos, activeFilter, creatorFilter, searchQuery]);
 
   const load = useCallback(async (isAutoRefresh = false) => {
     if (!isAutoRefresh) setLoading(true);