attachMonitor

Attach a Monitor to BackgroundTaskManager.events. The collector coroutine runs on scope; cancelling either scope or the returned AttachedMonitor tears the subscription down.

Scope ownership (CLAUDE.md §3). The collector is a child of scope, so cancellation propagates through structured concurrency. Pick a scope tied to a sensible lifetime — typically a ViewModel scope, an app-level scope, or a test's scope. Never GlobalScope.

Multiple monitors. Each call attaches an independent collector; monitors do not share state or back-pressure. The core's MutableSharedFlow is hot and non-replaying — late attachers see events emitted after their attach point, never before.

Exceptions. A Monitor.onEvent that throws does not cancel the subscription, and never propagates into scope — a misbehaving monitor must not take down the caller's sibling jobs. The event is dropped and the error logged via Kermit. Cancellation (of scope or the returned AttachedMonitor) still tears the collector down normally.