Add BFS flood-fill blob extraction, centroid finding, and nearest-neighbour track matching/spawning inside cv_process. Add test verifying a new blob spawns a track. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Add BFS flood-fill blob extraction, centroid finding, and nearest-neighbour track matching/spawning inside cv_process. Add test verifying a new blob spawns a track. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>