docs(inflight) #225: record the three-PR stack the feature now lands as, and take the note off deferred

The note said the work was deferred to after v6; it is in flight as #426
(this rung), #410 (recovery, stacked on it) and
#420 (the rest of producer ownership, stacked on recovery). Absent state
means open, so the deferred line goes and the stack is listed where the next reader looks first.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01VrpH51xNDodaajE4P2nhFg

Author: astubbs

docs/inflight/core-recoverable-producer-fencing.md

@@ -2,7 +2,21 @@
 
 <!-- inflight-type: feature -->
 <!-- inflight-impact: reliability -->
-<!-- inflight-state: deferred - after v6, nothing breaks by shipping without it -->
+
+## In flight as a stack of three PRs (2026-09-03)
+
+- astubbs/parallel-consumer#426 - `producerConfig`: PC builds its producer from configuration with the
+  default constructor, the caller's `transactional.id` included. The only rung recovery needs, because
+  re-initialising a replacement under the same id is what fences the producer it replaces.
+- astubbs/parallel-consumer#410 - recovery: detection, the aborted-transaction ledger and replay, the
+  replacement with backoff, observability, the broker IT. Stacked on astubbs#426.
+- astubbs/parallel-consumer#420 - the rest of producer ownership: a derived prefix-free
+  `transactional.id`, a `ProducerFactory` with an enforced contract, configuration redaction, deprecating
+  the instance option, migrating the examples. Stacked on astubbs#410.
+
+The plan the stack implements is `docs/plans/2026-09-02-001-feat-recoverable-producer-fencing-plan.md`,
+which arrives with astubbs#410. What follows is the note as it read before the work started.
+<!-- file-refs: N/A - the plan lands with astubbs#410, above this rung in the stack -->
 
 
 > Extracted from `origin/docs/session-learnings-857-family` @94bb98a9d, `docs/inflight/core-recoverable-producer-fencing.md`.