Your Worker reaches each sandbox by name. The runtime does not record which names belong to which user, and it does not wake a Durable Object when its container stops. To list a user's sandboxes or act when a sandbox stops, your Worker keeps its own records.
- List a user's sandboxes: Record each user's sandboxes in a Durable Object, and report which ones are running.
- Run code when a sandbox stops: Record when and why a sandbox stops, including stops that happen while no requests arrive.