add CMake dependency handling for portability

code/deps/Cmakelists.txt

@@ -0,0 +1,27 @@
+# deps/CMakeLists.txt
+function(setup_dependency NAME  SUBDIR)
+    if(NOT EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/${NAME}")
+        file(MAKE_DIRECTORY "${NAME}")
+        file(GLOB TARBALL "${CMAKE_CURRENT_SOURCE_DIR}/tarballs/${NAME}.tar.*")
+        message(STATUS "${CMAKE_CURRENT_SOURCE_DIR}")
+        if(NOT TARBALL)
+            message(FATAL_ERROR "❌ No '${NAME}*.tar.*' in deps/tarballs/")
+        else()
+    
+        message(STATUS "${CMAKE_COMMAND}  ${TARBALL}" )
+            execute_process(COMMAND "${CMAKE_COMMAND}" -E tar xf "${TARBALL}" "${NAME}/${SUBDIR}"  RESULT_VARIABLE TAR_STATUS  WORKING_DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}" )
+            message(STATUS "Extracting ${NAME}... Output: ${TAR_OUTPUT} Status: ${TAR_STATUS}")
+            if(NOT TAR_STATUS EQUAL 0)
+                message(FATAL_ERROR "❌ Extract failed: ${NAME}")
+            endif()        
+        endif()
+    else()
+        message(STATUS "✅ ${NAME} already exists, skipping extraction.")
+    endif()
+endfunction()
+
+setup_dependency("CGAL-6.1.1" "include" )
+setup_dependency("eigen-3.4.0" "Eigen"  )
+setup_dependency("boost_1_90_0" "boost"  )
+
+