Supported macOS containment for a sandboxed worker after controller failure.

Subject: Supported macOS containment for a sandboxed worker after controller failure

I'm investigating an Apple Silicon/macOS architecture in which an untrusted, signed, sandboxed worker must be independently containable by a separate trusted supervisor.

The worker needs only a narrow authenticated communication channel. It requires no direct network access, external operational credentials, privileged file access or authority to launch helpers.

I understand that App Sandbox does not inherently prevent child-process creation, and that RLIMIT_NPROC alone does not prevent every form of execution delegation.

Could you clarify:

1. Is there a public, supported macOS mechanism to deny all worker-originated subprocess creation and execution delegation at launch, while retaining one restricted communication channel?
2. Alternatively, is there a supported mechanism for a surviving supervisor to identify, terminate and positively verify the complete execution domain of a worker, including any descendants, after its controller crashes or is suspended?
3. What guarantees and limitations apply to stable identity, process exit, automatic relaunch and loss of the supervisor?

I'm specifically seeking supported operating-system guarantees, not private sandbox profiles, polling, heartbeat inference or best-effort process-tree enumeration.

The goal is to determine whether a bounded synthetic containment experiment is technically justified. No production implementation has been attempted.