Surface ready tasks that nobody claims within a threshold (default
30 min) regardless of why. One identity-agnostic signal that catches:
- Operator typo'd the assignee
- Profile was deleted, leaving its tasks stranded
- External worker pool (Codex CLI lane, custom daemon) is down
- Dispatcher misconfigured (wrong board / wrong HERMES_HOME)
Today the dispatcher correctly skips these (no respawn loop, good)
but nothing surfaces the fact that operator-actionable work is
accumulating. The new `stranded_in_ready` rule does that without
requiring a manual lane registry — it reads the most recent ready-
transition event (`created` / `promoted` / `reclaimed` / `unblocked`)
and fires when (now - last_ready_ts) > threshold.
Severity escalates with age: warning at threshold, error at 2x,
critical at 6x. The cli_hint and reassign actions point operators
at the right next step.
Out of scope deliberately:
- Lane registry (#20157 closed) — this signal supersedes it.
- Pushing the diagnostic into messaging gateways — diagnostics
are pull-only via 'hermes kanban diagnostics' for now; gateway
push is a separate UX decision.
Tests: 10 new + 461 existing kanban tests pass. E2E verified end-
to-end via 'hermes kanban diagnostics --json' against a 2h-old
stranded task — surfaces as error severity with correct actions.