fix incorrect var name

frontend/src/pages/StreamControl.tsx

@@ -62,7 +62,7 @@ const StreamControl = () => {
     const [jobs, setJobs] = useState<TrackedJob[]>([]);
 
     const isStreaming = streamStatus?.isStreaming ?? false;
-    const startMs = streamStatus?.startDate ? stringToDate(streamStatus.startDate).getTime() : null;
+    const startMs = streamStatus?.startTime ? stringToDate(streamStatus.startTime).getTime() : null;
     const elapsedSeconds = startMs === null ? 0 : Math.max(0, (now - startMs) / 1000);
     const elapsed = formatTimecode(elapsedSeconds);
 
@@ -127,12 +127,10 @@ const StreamControl = () => {
     const offsetOf = (marker: Marker) =>
         startMs === null ? 0 : (stringToDate(marker.timestamp).getTime() - startMs) / 1000;
 
-    // Ticking two markers fills the range. Done here rather than in an effect so a
-    // marker poll can't stomp on timecodes the user has since typed over.
+
     const toggleMarker = (id: number) => {
         const next = selected.includes(id)
             ? selected.filter((current) => current !== id)
-            // Third tick replaces the older of the two.
             : selected.length < 2 ? [...selected, id] : [selected[1], id];
 
         setSelected(next);
@@ -173,8 +171,6 @@ const StreamControl = () => {
         setMarkerBusy(true);
         setMarkerError(null);
         try {
-            // Dropping first and naming later isn't possible — markers have no PATCH —
-            // so an unnamed marker keeps the timecode it landed on.
             await createMarker(markerMessage.trim() || `Marker at ${elapsed}`);
             setMarkerMessage("");
             refreshMarkers();