Step 9: 2-CTA Cluster — Code

Same three-role structure as Step 7 — only highlighted lines change

TMA Producer (WG1/warp3)

MMA Consumer (WG1/warp0)

Writeback (WG0)

Key changes: CTA_GROUP=2 · remote_view(0) for cross-CTA barrier · cbx==0 guards · cta_mask=1→3 · cluster_sync