Design logging updates to support anomaly detection with Decoupling workers feature enabled

Evaluate the changes required to ensure anomaly detection continues to operate correctly after enabling the worker decoupling feature. This includes investigating logging gaps, required schema changes, and any new signals needed.

No files, tests, or entry points are named. Start by tracing the decoupling workers feature alongside anomaly detection, then investigate logging gaps, schema changes, and new signals; done means anomaly detection continues to operate correctly with worker decoupling enabled.

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