V45.17: fix seek khi play master FX active - set startOffsetTimeRef + __fxRtPlayheadFreeze NGAY tai click (het 50ms dau playhead chay theo processed anchor cu truoc khi dung) v=202608311151

app/static/js/app.jsx

@@ -19405,11 +19405,14 @@ const App = () => {
   const applyPlayheadDirect = (time) => {
     localSelectionAnchorRef.current = time;
     if (isPlaying) {
+      // V45.17: seek khi đang play — startOffset + freeze NGAY: playhead nhảy
+      // tới click + đứng tại đó (không chạy theo processed anchor cũ 50ms).
+      startOffsetTimeRef.current = time;
       setCurrentTime(time);
       fxRtKeepForRestart = true; // restart/resume — giữ session FX realtime
       stopAllPlayback();
+      try { if (window.__fxRtPlayheadFreeze) window.__fxRtPlayheadFreeze(true); } catch (e) { }
       setTimeout(() => {
-        startOffsetTimeRef.current = time;
         startAudioTimeRef.current = getAudioContext().currentTime;
         startTrackPlayback(time);
         setIsPlaying(true);

app/templates/index.html

@@ -51,7 +51,7 @@
     <script src="/static/js/services/promptTemplateManager.js?v=202608290945"></script>
     <script src="/static/js/services/undoRedoEngine.js?v=202608290945"></script>
     <script src="/static/js/services/chordTheory.js?v=202608290945"></script>
-    <script src="/static/js/app.precompiled.js?v=202608311143" defer></script>
+    <script src="/static/js/app.precompiled.js?v=202608311151" defer></script>
     <link rel="stylesheet" href="/static/css/styles.css?v=202608290945">
     <style>
         :root {