Merge feature/lts-viewer-validation-testing-phase into feature/qt6-migration-basis-modules-merge
Resolves 1 conflict (new_docker_build.sh, union of viewer-only + codification options); folds in fixes for pre-existing defects surfaced by the validation runs (KDReports-qt6 wiring, LtsSession RTI linking, LtsFileDialog/WLS/BSM Qt6/RTI API migration, GROUP4 target list, new --cmake_build_flags option); validated with BUILD_RTI=ON BUILD_GRANTLEE=ON in 3 Docker runs (run 3: build green, 6 base-state first-run CTest failures documented).
berrux-dev
9c1ac7cbef