That runs in a systemd task, so you can stop it with systemctl stop bela_ide and/or disable it at boot with systemctl disable bela_ide. However, if you just want to see its log, use journalctl -fu bela_ide. The mode switches detector used to be implemented with a clever C program, but that would no longer work in Xenomai 3, so we resorted to the old good way of cuting /proc/xenomai/sched/stat. This is implemented in function _CPU(data) in Bela/IDE/public/js/bundle.js, which is bundled together from Bela/dev/src/Views/ToolbarView.js.
If you really want to edit the code of the IDE, the proper way of doing it involves gulp and some setup: https://github.com/BelaPlatform/Bela/wiki/Developing-for-the-IDE
However for your purposes you can probably just cat /proc/xenomai/sched/stat | grep bela-audio | sed "s/ \{1,\}/ /g | cut -f " " X where "X" is the number of the column "MSW" in /proc/xenomai/sched/stat.
