V45.19: fix Bug 1b (seek#2 + wrap freeze) + Bug 2 (ARM scope theo active tab) v=202608311242

- Bug 1b: worklet clear_queue nho clearMode; dbgPlayFirst post fx_seek_first khi
  mode=seek -> main snap khong can guard 50ms (seek resume nhanh ~43ms < 50ms).
- Bug 1b: loop wrap KHONG freeze playhead nua (chi re-anchor processed) -> het
  playhead dung ~1.5s sau wrap (truoc day freeze 1500ms fail-safe).
- Bug 2: vkbNoteOn chi gom ARM piano roll khi DANG o PIANO_ROLL tab; MAIN/SECTION
  khong ARM -> targets rong -> preview cam. renderKeybed silent flag tuong tu.
- DIAG: preview_diag them trg/prTab (vkb) + sl (keybed).

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=202608311222" defer></script>
+    <script src="/static/js/app.precompiled.js?v=202608311242" defer></script>
     <link rel="stylesheet" href="/static/css/styles.css?v=202608290945">
     <style>
         :root {