Preserve user material names in convert_to_multigroup and avoid overw… #8675

Job	Run time
filter-changes	7s
Python 3.12 (omp=n, mpi=n, dagmc=n, libmesh=n, event=n	22m 19s
Python 3.14 (omp=n, mpi=n, dagmc=, libmesh=, event=	24m 1s
Python 3.12 (omp=y, mpi=n, dagmc=, libmesh=, event=y	54m 50s
Python 3.12 (omp=y, mpi=n, dagmc=n, libmesh=n, event=n	31m 46s
Python 3.13 (omp=n, mpi=n, dagmc=, libmesh=, event=	21m 36s
Python 3.12 (omp=y, mpi=y, dagmc=, libmesh=y, event=	44m 23s
Python 3.12 (omp=y, mpi=n, dagmc=, libmesh=y, event=	49m 5s
Python 3.12 (omp=n, mpi=y, dagmc=n, libmesh=n, event=n	28m 23s
Python 3.14t (omp=n, mpi=n, dagmc=, libmesh=, event=	26m 41s
Python 3.12 (omp=y, mpi=y, dagmc=n, libmesh=n, event=n	35m 26s
Python 3.12 (omp=y, mpi=y, dagmc=y, libmesh=, event=	49m 57s
coverage	11s
Check CI status	4s
	6h 28m 49s

Provide feedback