ComfyUI's default LoRA folders already pass the folder guard; a refused one
that exists is now listed in the layout's refused_defaults, and the layout
cache warns once per newly refused folder. The cache writes one INFO line
when a stored layout differs from the last one logged. BAD_SIDECAR_ROOT and
the module docstring name a folder that contains the home folder. A relative
preview_url writes a DEBUG line before the suffix search; a non-OSError
failure while loading trigger words logs its traceback. Review follow-ups
harden two serve tests.