docs: update MIGRATION_STATUS.md with Session 024 results

- Qt5:: CMake references cleanup complete
- LtsWidgets CMakeLists_rc.txt migrated to Qt6::
- SIGNAL/SLOT legacy syntax assessment (low priority)
- Module structure verification (TetraIF, Z)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Entire-Checkpoint: 01M0WHQDDTVBKTQ01R992EQ9KY

MIGRATION_STATUS.md

@@ -1,5 +1,50 @@
 # Qt5/C++11 → Qt6/C++17 Migration Status
 
+## Session 024: Qt5:: CMake References Cleanup Complete (2026-08-24)
+
+### ✅ All Qt5:: CMake References Migrated to Qt6::
+
+Final cleanup of Qt5:: CMake references in qt6-after directory completed:
+
+**Files Updated:**
+1. **Lts/Common/LtsWidgets/CMakeLists_rc.txt**
+   - Qt5::Network → Qt6::Network
+   - Qt5::Svg → Qt6::Svg
+   - Qt5::Core → Qt6::Core
+   - Qt5::Widgets → Qt6::Widgets
+   - Qt5::Gui → Qt6::Gui
+
+**Verification:**
+```bash
+$ grep -r "Qt5::" qt6-after/qt6-migrated-legatus/ --include="*.txt" --include="*.cmake"
+# Zero results - all Qt5:: references migrated
+```
+
+**SIGNAL/SLOT Status:**
+- Legacy string-based `connect(..., SIGNAL(...), ..., SLOT(...))` found in:
+  - `Lts/Tools/LoginTest/login_window.cpp` (6 instances)
+  - `Lts/Tools/CnrProxyTester/mainwindow.cpp` (1 commented)
+  - `Lts/Tools/VapixConfig/vapixconfig.cpp` (1 commented)
+- **Assessment**: Deprecated but functional in Qt6. Low priority migration.
+- **Q_SIGNALS/Q_SLOTS declarations**: All Qt6-compatible (no action needed)
+
+**Module Structure Verification:**
+- ✅ TetraIF: 115 files in both qt5-before and qt6-after (100% match)
+- ✅ Z module: 134 qt5 → 136 qt6 (2 new test files added)
+- ✅ All Lts modules present in qt6-after
+
+**C++17 Constraint (HARD BLOCKER):**
+- RTI Connext DDS 7.7.0 only supports C++14/C++17
+- C++20/C++23 causes header compilation errors in vendor headers
+- All build configurations standardized to C++17
+- BUILD_RTI=OFF allows development without RTI license
+
+**Commits:**
+- Submodule: `ec83f017b` (cmake: migrate Qt5:: to Qt6:: in LtsWidgets CMakeLists_rc.txt)
+- Main repo: `b121eead` (submodule: update qt-migration-legatus to ec83f017b)
+
+---
+
 ## Session 023: Lts/Tools QRegExp Migration Complete (2026-08-24)
 
 ### ✅ QRegExp → QRegularExpression Migration in Lts/Tools