build(aluminum): Add HeFFTe linking with fallbacks

Link HeFFTe explicitly to aluminumNew and aluminumTest
since OpenPFC now links it privately. Supports multiple
target variants with graceful fallback to find_package.

- Add HeFFTe to aluminumNew and aluminumTest link lines
- Check for Heffte::Heffte, Heffte, or heffte targets

Author: ahojukka5

apps/aluminumNew/CMakeLists.txt

@@ -14,7 +14,15 @@ if(CMAKE_PROJECT_NAME STREQUAL PROJECT_NAME)
 endif()
 
 add_executable(aluminumNew aluminumNew.cpp)
-target_link_libraries(aluminumNew OpenPFC nlohmann_json::nlohmann_json)
+if(TARGET Heffte::Heffte)
+    target_link_libraries(aluminumNew OpenPFC nlohmann_json::nlohmann_json Heffte::Heffte)
+elseif(TARGET Heffte)
+    target_link_libraries(aluminumNew OpenPFC nlohmann_json::nlohmann_json Heffte)
+elseif(TARGET heffte)
+    target_link_libraries(aluminumNew OpenPFC nlohmann_json::nlohmann_json heffte)
+else()
+    target_link_libraries(aluminumNew OpenPFC nlohmann_json::nlohmann_json)
+endif()
 
 # Only build tests if tests are enabled for the parent project
 option(ALUMINUM_ENABLE_TESTS "Enable building Aluminum tests" ON)
@@ -23,7 +31,15 @@ if(ALUMINUM_ENABLE_TESTS AND OpenPFC_BUILD_TESTS)
     find_package(Catch2 QUIET)
     if(TARGET Catch2::Catch2WithMain)
         add_executable(aluminumTest aluminumTest.cpp)
-        target_link_libraries(aluminumTest OpenPFC nlohmann_json::nlohmann_json Catch2::Catch2WithMain)
+                if(TARGET Heffte::Heffte)
+                    target_link_libraries(aluminumTest OpenPFC nlohmann_json::nlohmann_json Heffte::Heffte Catch2::Catch2WithMain)
+                elseif(TARGET Heffte)
+                    target_link_libraries(aluminumTest OpenPFC nlohmann_json::nlohmann_json Heffte Catch2::Catch2WithMain)
+                elseif(TARGET heffte)
+                    target_link_libraries(aluminumTest OpenPFC nlohmann_json::nlohmann_json heffte Catch2::Catch2WithMain)
+                else()
+                    target_link_libraries(aluminumTest OpenPFC nlohmann_json::nlohmann_json Catch2::Catch2WithMain)
+                endif()
         include(CTest)
         # Run all aluminum tests in a single invocation to avoid per-test MPI overhead
         add_test(NAME aluminum-all-tests COMMAND aluminumTest)