Bug hunt findings:
- epsilon_greedy_kernel.cu: all 3 kernels (select, routed, branching) lacked
the Q-gap conviction filter. Training learned with q_gap=0.1 but inference
paths bypassed it entirely. Now all action selection paths are consistent.
- c51_loss_kernel.cu: Bellman projection boundary fix — b_pos clamped away
from exact NUM_ATOMS-1 to prevent phantom upper==lower atom collapse.
- experience_kernels.cu: NaN/Inf guards on DSR and normalized PnL outputs.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
4f5daaa755