t8code Feature multiple attributes ghost commit from stash

Describe your changes here:

All these boxes must be checked by the reviewers before merging the pull request:

As a reviewer please read through all the code lines and make sure that the code is fully understood, bug free, well-documented and well-structured.

[ ] The reviewer executed the new code features at least once and checked the results manually
[ ] The code follows the t8code coding guidelines
[ ] New source/header files are properly added to the Makefiles
[ ] The code is well documented
[ ] All function declarations, structs/classes and their members have a proper doxygen documentation
[ ] All new algorithms and data structures are sufficiently optimal in terms of memory and runtime (If this should be merged, but there is still potential for optimization, create a new issue)

[ ] The code compiles without warning in debugging and release mode, with and without MPI (this should be executed automatically in a github action)
[ ] All tests pass (in various configurations, this should be executed automatically in a github action)

If the Pull request introduces code that is not covered by the github action (for example coupling with a new library):
- [ ] Should this use case be added to the github action?
- [ ] If not, does the specific use case compile and all tests pass (check manually)

[ ] If a new directory with source-files is added, it must be covered by the script/find_all_source_files.scp to check the indentation of these files.
[ ] If this PR introduces a new feature, it must be covered in an example/tutorial and a Wiki article.

Jul 22 '24 08:07 lukasdreyer

Needs to be cleaned up. There are still debug statements and comments that should be cleaned up.

Jul 22 '24 13:07 holke

Closes #1114

Jul 22 '24 13:07 holke

@lukasdreyer Thank you for your work on this PR! Please see the review comments above. Also please resolve the merge conflict.

Aug 12 '24 13:08 jmark