pi0.5 RoboTwin clean50 SFT v2 (filtered-BC)

• Eval (official openpi stack, 15 base>0 tasks, n=10, seed 100100): 47.3% vs v1 45.3% — floor lifted (click_alarmclock .1->.5, place_a2b_right .1->.4), all 15 tasks >0.
• Intended use: RL (e.g. RLinf PPO) starting base / plain-SFT baseline.
• Files: model.safetensors (812-key pi0.5), assets/robotwin2/aloha_clean50_fbc_v1/norm_stats.json, metadata.pt. Optimizer omitted.