debug: Make the freezed properties clearly identifiable as such

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
libj4status-plugin: Micro reordering

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
nm: Micro cleanup

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
j4status-plugin.h: Fix NO_STATE

-1 is unsafe here since we now have flags which are likely to match it.

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>