new hive_c0re::crash_watch task polls every 10s, builds the set of
currently-running containers, and on running→stopped transitions
checks the transient snapshot: if no Stopping / Restarting /
Destroying / Rebuilding flag is set, the container exited
unexpectedly and we fire HelperEvent::ContainerCrash into the
manager's inbox so it can react (typically: start it again).
first poll is a seeding pass — no events on harness startup. dbus
subscription would be lower-latency but polling is honest and
debuggable, and a 10s delay on crash detection is fine for our
scale.
manager prompt + approvals doc updated to advertise the new
event variant. todo drops the entry (and the journald-viewer
entry that already shipped).
58c3cd853b