- Layer 1 now targets experience_action_select (GPU-fused training path)
AND branching_action_select (backtest/fallback), not just the fallback
- Action masking covers both greedy AND random exploration paths
- Exposure index uses parameterized b0_size, not hardcoded 5 or 9
- Fixed end-of-episode variable name (total_bars, not timesteps_per_episode)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>