Description

This command transitions a session to the Expired state when its time-to-live has elapsed. Typically invoked by a background cleanup process or lazily when an expired session is accessed.

Preconditions

• Session exists and is in Active state
• Current time exceeds the session’s expiresAt timestamp

Command handler behavior

The Decider’s decide function validates:

1. Session ID exists in current state
2. Session is Active (not already Expired or Invalidated)
3. Current time exceeds expiresAt

If validation passes, emits SessionExpired event. If session is already terminated, operation is idempotent.