The brain logs an event when something materially changes its behavior:
🎓 Training: A batch of new labeled data was processed and the weights shifted. Logged with loss delta.
⚠ Drift: Recent hit rate diverged from lifetime average by more than 8%. Could mean regime change.
🚀 Promotion: A new model version was promoted to production (replaced the active model).
🌱 Seed: Synthetic training data was generated (usually on first install or after a reset).
🔄 Reset: The brain was reset — all weights zeroed, training data preserved.

Events are persisted in localStorage. Use Clear log to wipe — this won't affect the model itself, just the audit trail.