Fix svcAesCommon: make situationMapElevationMap and Trajectory conditional

- Use TARGET_EXISTS generator expressions for external dependencies
- Allows building without Viewer/SituationMap module in Release 2
- Maintains compatibility when those modules are available

qt6-after/qt6-migrated-legatus/Lts/Services/AreaEffectSimulation/CMakeLists.txt

@@ -118,8 +118,8 @@ if(QT6_GUI_AVAILABLE)
       NGLLogger
       nglsettings
       ngltools
-      situationMapElevationMap
-      Trajectory
+      $<IF:$<TARGET_EXISTS:situationMapElevationMap>,situationMapElevationMap,>
+      $<IF:$<TARGET_EXISTS:Trajectory>,Trajectory,>
       ngldb
   )
 endif()