Fix 1 frame offset in clip monitor zone causing issues on timeline insert

src/monitor/monitor.cpp

@@ -876,7 +876,7 @@ void Monitor::slotStartDrag()
         QStringList list;
         list.append(m_controller->AbstractProjectItem::clipId());
         list.append(QString::number(p.x()));
-        list.append(QString::number(p.y()));
+        list.append(QString::number(p.y() - 1));
         prodData.append(list.join(QLatin1Char('/')).toUtf8());
     }
     mimeData->setData(QStringLiteral("kdenlive/producerslist"), prodData);

src/monitor/view/kdenliveclipmonitor.qml

@@ -329,7 +329,7 @@ Item {
                     Drag.active: dragVideoArea.drag.active
                     Drag.dragType: Drag.Automatic
                     Drag.mimeData: {
-                        "kdenlive/producerslist" : "V" + controller.clipId + "/" + controller.zoneIn + "/" + controller.zoneOut
+                        "kdenlive/producerslist" : "V" + controller.clipId + "/" + controller.zoneIn + "/" + (controller.zoneOut - 1)
                     }
                     MouseArea {
                         id: dragVideoArea