Track desired membership separately from active target state and make natural completion an explicit group policy. Empty authoritative updates now remove all targets without terminating the scheduler, while static CLI groups retain all-target completion.
Document that construction still requires an address-family-defining target and add regressions for empty replacement, later re-addition, idle control responsiveness, idle cancellation, and finite static completion.
Extend the managed group stream with authoritative per-target terminal outcomes and structured failure classifications. Final client events are published first, followed by exactly one TargetFinished outcome for success, peer close, no-test, opening/runtime failure, removal, or cancellation.
Scheduler-owned cleanup now stops the receiver and seals subscriptions on natural completion, eliminating the event-consumer/join circular wait while preserving queued drain. TargetEventSubscription now yields ManagedGroupEvent, so consumers must handle Client and TargetFinished variants.
Strict-timeout regressions cover mixed success/failure, all-open failure, runtime failure, no-test ordering, removal, cancellation, and disconnection before join.
Introduce a managed group runner to support concurrent probing of multiple targets over a single UDP socket with coordinated send pacing. Refactor the existing client logic into a reusable SessionRuntime to support both individual and grouped session management.
Nils Andreas Svee