decompose review-004 recorded findings: 15 disposition tasks + the review-004-fixes gate (sqlite seam panic-safety, watcher-death subscribe + initial-stat, bridge alignment, scheduler classification, substrate SAFETY delta; pg forwarder hardening + diagnosability, BIGINT stamp decision + fix, log-facade decision; core offset pin + Display forging, mem doc notes, pg identifier note, tokio dev-dep normalization) — taskgraph validate green (95)

tasks/mem-doc-growth-outbox-notes.md

@@ -0,0 +1,67 @@
+---
+id: mem-doc-growth-outbox-notes
+name: Pin mem's growth postures and outbox semantics in the spec (review 004 items 10+11)
+status: pending
+depends_on: []
+scope: narrow
+risk: trivial
+impact: isolated
+level: implementation
+tags: [review-004-fixes, mem-engine, docs]
+---
+
+## Description
+
+Two recorded mem postures get their doc pins, per
+`docs/reviews/004-pre-release-general-review.md` §"Findings recorded,
+not fixed" items 10 and 11 (the review's "carry into the mem spec's
+growth section when next touched" — this is that touch).
+
+**(a) Growth postures (item 10)** — two honest sentences in
+`engine-mem.md`'s growth section:
+- The subscribe path drains the full backlog into the receiver's
+  pending deque before the first yield, and pending grows at publish
+  rate for a stalled consumer (`stream.rs:314-331` — the documented
+  "drains to the tail then parks" shape, unbounded on the consumer
+  side).
+- The claim path is an O(total-live-rows) scan with full-row clones
+  per claim (`queue.rs:122-181`) — blessed economics for the ephemeral
+  tier.
+
+**(b) Outbox outcome swallow (item 11)** — `outbox run_once` drops the
+ack/retry row-refs' booleans and returns `Ok(true)` even when delivery
+outlived the visibility window and nothing landed (`outbox.rs:104-122`).
+Inherent to the no-heartbeat outbox design (at-least-once reclaim is
+the recovery). Pin the "processed means delivered-or-reclaimable"
+semantic with a doc sentence in `engine-mem.md`'s outbox section; add
+the `debug_assert!` too if it adds value without noise — the review
+offered either, implementer's call (record which and why).
+
+Doc-only plus at most one `debug_assert!` — no behavioral change.
+
+## Acceptance Criteria
+
+- [ ] `engine-mem.md` carries the two growth-posture sentences,
+      anchored to the code sites
+- [ ] The outbox "processed means delivered-or-reclaimable" semantic
+      is pinned (doc sentence; `debug_assert!` per the recorded call)
+- [ ] Doc gate green (`RUSTDOCFLAGS="-D warnings" cargo doc
+      --no-deps`); mem tests green (the `debug_assert!` arm, if added,
+      exercised by an existing outbox test)
+
+## References
+
+- docs/reviews/004-pre-release-general-review.md §"Findings recorded,
+  not fixed" items 10–11 (the findings, the blessed-economics framing)
+- docs/architecture/engine-mem.md (the growth section, the outbox
+  section)
+- alkstore-mem/src/stream.rs:314-331, queue.rs:122-181,
+  outbox.rs:104-122 (the anchored sites)
+
+## Notes
+
+> To be filled by implementation agent
+
+## Summary
+
+> To be filled on completion