Qt6 Migration: Merge latest Qt5 devel content and apply migration fixes

- Merged 292 changed files from dlbo snapshot
- Fixed IDL enum collisions (PortType, PdmEventType)
- Fixed Grantlee template for C++11 scoped enums
- Fixed CMake VERSION_GREATER syntax
- Added missing directories (THP, LtsRestClient, etc.)

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

Lts/Common/LtsPluginManager/lts_plugin_loader.cpp

@@ -258,7 +258,8 @@ bool LtsPluginLoader::loadPlugins(PluginType requestedPluginType,
                                         QStringLiteral("topic_type"),
                                         QStringLiteral("project"),
                                         QStringLiteral("style"),
-                                        QStringLiteral("special")}); // #warning TODO: recordreplay is a data plugin ?
+                                        QStringLiteral("special"),
+                                        QStringLiteral("gui_element")}); // #warning TODO: recordreplay is a data plugin ?
 
   QDirIterator pluginDir(libPath, nameFilter, QDir::Files);
   while (pluginDir.hasNext())
@@ -335,6 +336,9 @@ bool LtsPluginLoader::loadPlugins(PluginType requestedPluginType,
     case 5: // special
       pluginType = PluginType::SPECIAL;
       break;
+    case 6: // gui_element
+      pluginType = PluginType::GUI_ELEMENT;
+      break;
     default:
       break;
     }