Update app::ui_scene to use the legacy ui library

libs/app/CMakeLists.txt

@@ -1,6 +1,11 @@
 file(GLOB_RECURSE PSEMEK_APP_HEADERS RELATIVE "${CMAKE_CURRENT_SOURCE_DIR}" "include/*.hpp")
 file(GLOB_RECURSE PSEMEK_APP_SOURCES RELATIVE "${CMAKE_CURRENT_SOURCE_DIR}" "source/*.cpp")
 
+if(NOT PSEMEK_LEGACY_UI)
+	list(REMOVE_ITEM PSEMEK_APP_HEADERS "include/psemek/app/ui_scene_legacy.hpp")
+	list(REMOVE_ITEM PSEMEK_APP_SOURCES "source/ui_scene_legacy.cpp")
+endif()
+
 psemek_add_library(psemek-app ${PSEMEK_APP_HEADERS} ${PSEMEK_APP_SOURCES})
 target_include_directories(psemek-app PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/include")
 target_link_libraries(psemek-app PUBLIC psemek-log psemek-util psemek-gfx psemek-ui psemek-sdl2)