docs: resolve OQ-05 + OQ-09 — queue semantics depth (ADR-010) and scheduler collapse (ADR-009)

ADR-009: scheduler collapses into queues — schedule()/unschedule()/
run_schedules (opt-in, no ambient timers), @every-only v1 grammar
(dissolves honker's local-TZ cron brittleness), boundary guarantee
row (at-least-once per boundary, fixed 64-cap catch-up with
skip-forward, row-locked fire tx as engine-generic no-double-fire
floor), __alkstore_scheduler leadership lock, InvalidSpec +
LeadershipLost taxonomy additions.

ADR-010: queue depth pinned engine-uniformly — three-state machine
(pending/processing/dead) with delete-on-ack, get_job sees dead rows,
heartbeat = renewal with late-heartbeat refusal, reclaim-consumes-
an-attempt stated as contract text, equal-jitter exponential backoff
(range definitionally pinned, 1 h cap), QueueOpts stamped onto job
rows at enqueue (no per-queue registry), move-to-dead dead-letter
with retention-sweep support and no redrive API, sweep_expired
carries the no-stranded-rows property (fixes honker's expired-
processing zombie hole — SQLite-side realization rides OQ-06 as a
concrete fork candidate), one engine-owned pg schema, queues are
rows not tables, result-storage cut-flag stands.

Also: full honker-machinery and pgboss-rs reference reads persisted
(docs/research/reference-*.md — the honker defect list pre-stages the
OQ-06 quality read), queues.md rewritten from design-space frame to
resolved-depth spec, core-contract/engines/README/overview/deployment/
ADR-002 propagated.

docs/architecture/engine-postgres.md

@@ -26,7 +26,10 @@ obligations live in the core spec.
 - Queue machinery re-derived on this driver with the pg-boss schema
   family as design reference
   ([ADR-005](decisions/005-dependency-ownership.md)); semantics depth
-  is [queues.md](queues.md)'s work (OQ-05).
+  pinned by [ADR-010](decisions/010-queue-semantics-depth.md) — all
+  engine-owned tables (job, dead, stream, offsets, schedule) in one
+  PostgreSQL schema (default `alkstore`), queues as rows, no
+  per-queue tables.
 
 ## Connection architecture
 
@@ -62,9 +65,9 @@ obligations live in the core spec.
 |---|---|
 | notify / listen | `pg_notify(...)` inside the caller's tx (delivers at commit — native commit-atomicity, [ADR-007](decisions/007-transactional-seam.md)); `listen()` via LISTEN on the forwarder's connection, fanout to receivers |
 | streams | durable event table + per-consumer offset cursors; `pg_notify` as the wake trigger ([ADR-006](decisions/006-wake-and-delivery-contract.md) mechanism split: durable row, LISTEN wake — the pg-boss-family shape) |
-| queues | re-derived queue table + `FOR UPDATE SKIP LOCKED` claim + LISTEN-driven wake with re-poll safety net (default consumption posture, measured 5–16× vs 50 ms poll; poll-only fallback) |
-| named locks | advisory-lock-semantics TTL locks (pg-boss-family design reference; depth in OQ-05's design work) |
-| scheduler / outbox | pg-boss-family design reference, per [queues.md](queues.md) |
+| queues | re-derived queue table + `FOR UPDATE SKIP LOCKED` claim + LISTEN-driven wake with re-poll safety net (default consumption posture, measured 5–16× vs 50 ms poll; poll-only fallback); states/dead-letter/backoff/visibility per [ADR-010](decisions/010-queue-semantics-depth.md), all in the engine-owned schema |
+| named locks | advisory-lock-semantics TTL locks (pg-boss-family design reference; guarantee row pinned by [ADR-008](decisions/008-contract-v1-pinning.md) §7) |
+| scheduler / outbox | collapse shape ([ADR-009](decisions/009-scheduler-collapse.md)): schedule rows in the engine-owned schema, tick re-derived (boundary advance + 64-boundary catch-up cap, honker parity), leadership via the engine's lock machinery on `__alkstore_scheduler`; outbox = helper over queues |
 | begin_tx | pool checkout + `BEGIN`, returning the caller-held handle ([ADR-007](decisions/007-transactional-seam.md)) |
 | handle ops | straight `.await`s through the held object; commit/rollback returns the object to the pool |
 
@@ -103,6 +106,8 @@ the record in [ADR-003](decisions/003-sqlite-driver.md).
 | [006](decisions/006-wake-and-delivery-contract.md) | Wake contract | LISTEN push, no replay, synthetic reconnect-wake |
 | [007](decisions/007-transactional-seam.md) | Tx seam | direct pooled-object handle, no bridging |
 | [008](decisions/008-contract-v1-pinning.md) | Contract v1 | pinned surface; reserved reconnect-wake channel string; `PayloadTooLarge` taxonomy variant |
+| [009](decisions/009-scheduler-collapse.md) | Scheduler collapse | schedule rows in the engine schema, re-derived tick, row-locked fire tx, `__alkstore_scheduler` leadership |
+| [010](decisions/010-queue-semantics-depth.md) | Queue depth | job-stamped opts, equal-jitter backoff, dead-letter move, no-stranded-rows sweep, one engine-owned schema |
 
 ## Open Questions
 
@@ -110,9 +115,10 @@ Open questions are tracked in
 [open-questions.md](open-questions.md). Key
 questions affecting this document:
 
-- **OQ-09**: scheduler collapse into queues (shared with
-  [queues.md](queues.md)) (open)
-- **OQ-05**: queue semantics depth — the pg-boss-family design-input
-  work (open)
 - **OQ-08**: capability surface (shared with
-  [deployment.md](deployment.md)) (open)
+  [deployment.md](deployment.md)) (open)
+
+Resolved: **OQ-09** (scheduler collapse —
+[ADR-009](decisions/009-scheduler-collapse.md)) and **OQ-05** (queue
+semantics depth — [ADR-010](decisions/010-queue-semantics-depth.md)),
+2026-10-05.