Install into the target CMake root, not the host one.

diff -Nrup a/CMakeLists.txt b/CMakeLists.txt
--- a/CMakeLists.txt	2026-04-11 14:11:38.000000000 +0200
+++ b/CMakeLists.txt	2026-10-22 17:22:43.029339644 +0200
@@ -26,9 +26,9 @@ project( tde-cmake-rules )
 file( GLOB_RECURSE _modules
       RELATIVE ${CMAKE_CURRENT_SOURCE_DIR}
       ${CMAKE_CURRENT_SOURCE_DIR}/modules/* )
-install( FILES ${_modules} DESTINATION ${CMAKE_ROOT}/Modules )
+install( FILES ${_modules} DESTINATION share/cmake-${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION}/Modules )
 
 file( GLOB_RECURSE _templates
       RELATIVE ${CMAKE_CURRENT_SOURCE_DIR}
       ${CMAKE_CURRENT_SOURCE_DIR}/templates/* )
-install( FILES ${_templates} DESTINATION ${CMAKE_ROOT}/Templates )
+install( FILES ${_templates} DESTINATION share/cmake-${CMAKE_MAJOR_VERSION}.${CMAKE_MINOR_VERSION}/Templates )