fix: realtime note display + MIDI key sound via refs

app/static/js/app.jsx

@@ -6287,10 +6287,12 @@ const App = () => {
                 setLastMidiNote({ pitch, velocity, length: 0, time: Date.now() });
                 activeMidiPitchesRef.current.add(pitch);
                 setActiveMidiPitches(new Set(activeMidiPitchesRef.current));
-               const activeTabInfo = subTabs.find(s => s.id === activeTab && s.type === 'PIANO_ROLL' && s.isArmed);
-               if (activeTabInfo && window.SonicSF) {
-                 try { window.SonicSF.playNote(pitch, velocity, 500, undefined, activeTabInfo.instrumentProgram, null); } catch (e) {}
+                try {
+                  const ar = activeTabRef && subTabsRef && subTabsRef.current.find(s => s.id === activeTabRef.current && s.type === 'PIANO_ROLL' && s.isArmed);
+                  if (ar && window.SonicSF) {
+                    window.SonicSF.playNote(pitch, velocity, 500, undefined, ar.instrumentProgram, null);
                   }
+                } catch (e) {}
               } else if (cmd === 0x8 || (cmd === 0x9 && velocity === 0)) {
                 activeMidiPitchesRef.current.delete(pitch);
                 setActiveMidiPitches(new Set(activeMidiPitchesRef.current));
@@ -9867,8 +9869,6 @@ const App = () => {
     midiRec.onNoteOn = (pitch, currentBeat) => {
       const elapsedBeats = Math.max(0, currentBeat);
       const sec = elapsedBeats * (60.0 / (parseInt(bpm) || 120));
-      setSubTabs(prev => prev.map(s => {
-        if (s.id !== tab.id) return s;
       const activeNotes = Array.from(midiRec.activeNotes.values()).map(n => ({
         id: 'rec_' + n.pitch + '_' + currentBeat,
         pitch: n.pitch,
@@ -9888,8 +9888,9 @@ const App = () => {
       const allNotes = [...rec, ...activeNotes];
       setRecTempMidiNotes(allNotes);
       setCanvasRedrawCount(n => n + 1);
-        return { ...s, currentTime: startTime + sec, isDirty: true };
-      }));
+      setSubTabs(prev => prev.map(s =>
+        s.id === tab.id ? { ...s, currentTime: startTime + sec, isDirty: true } : s
+      ));
     };
     showToast('Recording MIDI to Piano Roll...', 'info');
   };