Clarify PULSE as tiny NERVE sibling

PAPER.md

@@ -7,9 +7,11 @@
 
 **A tiny, deployment-first super-resolution network.**
 
-PULSE is the speed/deployment tier of the **BODY** suite: a plain convolutional
-SISR model built to be trained on a consumer GPU, converted without surprises,
-and embedded almost anywhere.
+PULSE is the **tiny/fast sibling of NERVE**: a much smaller convolutional SISR
+model with the same deployment-first philosophy. It trades capacity for size and
+speed, so it is less capable than NERVE and is intended for light cleanup and
+clean upscaling rather than heavy restoration. It trains on a consumer GPU,
+converts without surprises, and embeds almost anywhere.
 
 - `pulse`: 48 channels, **353,856 parameters**
 - `pulse_fast`: 32 channels, **162,192 parameters**