Add TetraIF targets to GROUP6 and create compilation tests

- Add CoPrtCnv, PrtCnvLib, PrtCnv to GROUP6_TARGETS in new_docker_build.sh
- Clean up redundant find_package(Qt6) in CoPrtCnv/CMakeLists.txt
- Add CTest compilation tests for CoPrtCnv, LogView, and PrtCnv headers
- Tests verify Qt6/C++17 compatibility of TetraIF module headers

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

qt6-after/qt6-migrated-legatus/tests/test_tetraif_coprtcnv.cpp

@@ -0,0 +1,21 @@
+/**
+ * @file test_tetraif_coprtcnv.cpp
+ * @brief Compilation test for TetraIF/CoPrtCnv headers
+ *
+ * This test verifies that the migrated CoPrtCnv headers compile correctly with Qt6/C++17.
+ */
+
+#include "TetraIF/CoPrtCnv/CoPrtCnvLogHeader.hpp"
+#include "TetraIF/CoPrtCnv/CoPrtCnvRadioTelegram.hpp"
+#include "TetraIF/CoPrtCnv/CoPrtCnvHexDumpHelper.hpp"
+#include "TetraIF/CoPrtCnv/CoPrtCnvInjectionHeader.hpp"
+#include "TetraIF/CoPrtCnv/CoPrtCnvCentralTelegram.hpp"
+#include "TetraIF/CoPrtCnv/CoPrtCnvTelegramConverter.hpp"
+
+#include <gtest/gtest.h>
+
+TEST(TetraIF_CoPrtCnv, HeadersCompile)
+{
+    // This test verifies that the CoPrtCnv headers compile without errors
+    EXPECT_TRUE(true);
+}