Fix Geant4.xenv generation for legacy CMake compatibility

CMakeLists.txt

@@ -57,7 +57,9 @@ if(GAUDI_LEGACY_CMAKE_SUPPORT)
   # This is to match Geant4 install layout
   install(FILES
     ${PROJECT_BINARY_DIR}/.metadata.cmake
+    ${PROJECT_SOURCE_DIR}/source/lhcb/Geant4.xenv
     DESTINATION ${GEANT4_CMAKE_DIR}
     COMPONENT Development
   )
+  message(STATUS "GEANT4_CMAKE_DIR -> ${GEANT4_CMAKE_DIR}")
 endif()

source/lhcb/Geant4.xenv

+<?xml version="1.0" encoding="UTF-8"?>
+<env:config xmlns:env="EnvSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="EnvSchema EnvSchema.xsd ">
+  <env:include>../../Geant4.xenv</env:include>
+  <env:prepend variable="PATH">${.}/../../bin</env:prepend>
+  <env:prepend variable="LD_LIBRARY_PATH">${.}/..</env:prepend>
+  <env:prepend variable="ROOT_INCLUDE_PATH">${.}/../../include</env:prepend>
+</env:config>