Audit logs #126

docs/compatibility.md lists audit logs as not provided. Operator actions (deploy, restore, drain, object inspection) are not recorded in a durable, queryable form.

Do

• Define the event set and the retention model.
• Record actor, action, target and outcome for admin and lifecycle operations.
• Decide where they live (state directory vs. bucket) and how they are exported.

Done when

Operator actions are recorded and retrievable, and the format is documented.