Stale pid condition after service collection leaves dependents stuck

[troglobit]

When a service crashes or is killed (e.g., SIGKILL), it transitions directly from RUNNING to HALTED, bypassing the STOPPING state where cond_clear() is normally called. This means the service's pid/ condition is never invalidated, and dependent services are never notified that the condition went away.

The pidfile plugin cannot help here either — it only watches for IN_CLOSE_WRITE events, so the IN_DELETE from pidfile removal in service_cleanup() is never delivered.

In a chain like:

A ← B <pid/A> ← C <pid/B>

Killing B with kill -9 causes B to be collected and respawned, but pid/B is never cleared. C never sees the condition go OFF and is never restarted, even though B got a new PID.