s_create_directory called with /* wildcard creates junk directory

[sbryngelson]

Bug

In src/pre_process/m_start_up.fpp line 508, s_create_directory is called with a /* suffix:

! "cleaned out to make room for new pre-process data"
call s_create_directory(trim(proc_rank_dir)//'/*')

s_create_directory runs mkdir -p "path/*", which creates a literal directory named * inside proc_rank_dir. The comment says "cleaned out" — the intent was to remove old files, not create a junk directory. Old data files happen to get overwritten by subsequent writes so this doesn't crash, but it leaves a * directory behind and doesn't actually clean stale files.

Fix

PR #1214