Smoke test loads all hyperparams from TOML profile instead of hardcoding. TOML: hidden_dim=64, batch=64, lr=0.0003 (stable on RTX 3050 + H100). Restored check_err() drain in device.rs — required to clear stale CUDA errors from primary context reuse between tests. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>