The DNN velocity grid (radius vel_radius) extends past the trained velocity
disk, so untrained corner cells emit spurious sidelobes (ghosts) of non-trivial
strength (s up to ~0.09) that would confuse the recurrent layer. New
dnnGhostbust() zeros velocity cells with cell-radius > curt_dnn_vmax*vel_decimate,
and if a pixel's peak lands in the untrained corner it discards the whole
detection (field=0, s=0). Applied to the DNN field + offset before save and the
recurrent feed. New param curt_dnn_vmax (px/frame, default 1.4 = PM models'
training vmax_px; set to match the loaded model; <=0 disables).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>