- metrics.rs: fallback action_space was hardcoded 5 (old non-branching).
Changed to 9 (exposure levels). Branching is always active.
- smoke_test_real_data: assertion updated to accept >=9 action space
(81 with factored counts, 9 for short runs with empty factored counts)
- gpu_smoketest: added missing adam_epsilon field
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>