Migrates AudioVideoManagement to generated rtiddsgen API

Converts accessor calls to plain member access across avm service and plugin.

qt6-after/qt6-migrated-legatus/Lts/Services/AudioVideoManagement/ava_comm.cpp

@@ -141,7 +141,9 @@ void AvaComm::queryTimeline(const QString &streamName, const boost::optional<Ava
 void AvaComm::setVolume(AvaVolume db)
 {
   static const QString   cmd = QStringLiteral("setVolume 1 %1");
-  m_avSocket.send(cmd.arg(db).toUtf8());
+  // Qt6 QString::arg is enable_if-constrained to arithmetic types and no
+  // longer picks up the implicit operator int() of AvaVolume.
+  m_avSocket.send(cmd.arg(int(db)).toUtf8());
 }
 
 void AvaComm::startStream(const QString &dialogId, const QString &streamName, AvaSpeed speed)