cluster: faiss-gpu has no Blackwell kernels — CPU faiss + torch-GPU recluster_torch.py (reuses cached emb)

maxact-fast: hardening fixes (6 bugs) + Dr.GRPO vllm-lens rl.py + sbatch; Probe = universal direction

maxact-fast: clean repo — DESIGN + pretraining pipeline (embed/cluster/probe-cache/build-data/pretrain), Dr. GRPO RL to follow