Say which operator actions are debt and which are just operations

An intervention is an action required to recover, repair, unblock or correct
behaviour that should have proceeded on its own. A deploy restart, a planned
upgrade and burn-in setup are none of those, and recording them would inflate
operator cost with work Orchestra is expected to need.

Policy rather than schema. worker_restart is the one kind that spans both
sides, and it stays one kind until someone actually misuses it.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01CVbaKucEYBjMqVeUgJUsc1

DEBT-DESIGN.md

@@ -441,3 +441,41 @@ That is the intended behavior. An event must not silently change meaning
 because normalization code changed. Repairing historical signatures is an
 explicit migration or reclassification event, never a different projection
 result from the same log.
+
+## What counts as a manual intervention
+
+An intervention is an operator action required to recover, repair, unblock or
+correct behaviour that should otherwise have proceeded autonomously. The
+ledger measures what the system costs to keep running, so routine operation
+does not belong in it.
+
+Counts:
+
+```text
+transaction_cleanup
+forced_release
+state_repair
+manual_requeue          when recovery failed and a human had to requeue
+manual_phase_recovery
+worker_restart          only when restarting is itself the repair
+```
+
+Does not count:
+
+```text
+deploy restart
+planned upgrade
+configuration rollout
+normal shutdown and start
+deliberate burn-in setup
+```
+
+The distinction is policy rather than schema. `worker_restart` is the one kind
+that spans both sides, and it stays a single kind until someone actually
+misuses it; a field added before the confusion exists is a guess about how it
+will be misread.
+
+The first live consequence: the deploy restart of `79d2053` was not recorded,
+and `manual_intervention` stayed in the gap list afterwards. That is the
+correct result. Orchestra can record the evidence and this history contains
+none, which is an honest gap rather than synthetic evidence.