- Delete 7 dead files: prioritized_replay.rs, prioritized_replay_staleness.rs,
replay_buffer.rs, hindsight_replay.rs, rainbow_agent.rs, checkpoint.rs,
strategy_dqn_bridge.rs (-4,760 lines)
- Rewrite replay_buffer_type.rs: ReplayBufferType enum → StagedGpuBuffer struct
(GPU PER is the only replay path, no CPU fallbacks)
- Strip agent.rs to data types only (TradingState + AgentMetrics)
- Convert DQNAgentType from enum to struct wrapping RegimeConditionalDQN
(Standard variant was never constructed, 43 dead match arms removed)
- Remove dead CPU methods: store_experience, fused_post_step,
fused_post_step_no_ema, adaptive_buffer_resize, refresh_stale_per_priorities
- Add always-on CUDA event per-phase profiling (8 events, 4 phases:
upload/fwd_bwd/adam/per_update) with Drop cleanup and error checking
to identify 329ms/batch H100 bottleneck
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
e265768cb3