Add BUILD_RTI guards to InfrastructureManagement and AudioVideoManagement DDS handlers

- ism_dtc_impl_custom.h/cpp: Wrap all DDS-dependent method declarations and implementations with BUILD_RTI guards
- dds_handler.cpp (InfrastructureManagement): Guard RTI DDS initialization code
- dds_handler.h/cpp (AudioVideoManagement): Guard DomainParticipant types and methods
- Enables building without RTI Connext DDS dependencies (BUILD_RTI=OFF)
- Stub types used when guards are disabled

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

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

@@ -18,7 +18,9 @@
 #include <InfrastructureManagement/ism_dtc.h>
 
 #include <DDS/DDSConnector/dds_connector.h>
+#if BUILD_RTI
 #include <DDS/Core/pacemaker.h>
+#endif
 
 
 namespace AudioVideoManagement
@@ -38,6 +40,7 @@ bool DdsHandler::init(const QStringList &qosFileList)
     return false;
   }
 
+#if BUILD_RTI
   // default initialize Publisher and Subscriber
   m_ddsConnector->initPublisherSubscriber();
   // no batched writer possible until frequency set data is no longer that big (currently 1800rows)
@@ -57,6 +60,9 @@ bool DdsHandler::init(const QStringList &qosFileList)
   bRet &= m_fts->enableAll();
 
   return bRet;
+#else
+  return true;
+#endif
 }
 
 bool DdsHandler::enableDtcClients()
@@ -64,6 +70,7 @@ bool DdsHandler::enableDtcClients()
   Q_ASSERT(m_exmDtc);
   Q_ASSERT(m_ismDtc);
   Q_ASSERT(m_asmDtc);
+#if BUILD_RTI
   bool   status = m_exmDtc->enableExercise() &&
                   m_ismDtc->enableInstrumentationAsset() &&
                   m_ismDtc->enableMainStructureElement() &&
@@ -72,11 +79,16 @@ bool DdsHandler::enableDtcClients()
   Q_ASSERT(status);
 
   return status;
+#else
+  return true;
+#endif
 }
 
+#if BUILD_RTI
 dds::domain::DomainParticipant DdsHandler::domainParticipant() const
 {
   return m_ddsConnector->getDomainParticipant();
 }
+#endif
 
 } // Namespace AudioVideoManagement