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/README.md

@@ -24,10 +24,10 @@ pending architecture review and OQ resolution.
 | Doc | Status | Purpose | Key OQs |
 |---|---|---|---|
 | [overview.md](overview.md) | draft | Crate family, feature surface, non-goals, evidence base | — |
-| [core-contract.md](core-contract.md) | draft | The unified trait surface, delivery guarantees, tx seam | OQ-05, OQ-08, OQ-09, OQ-10 |
-| [engine-sqlite.md](engine-sqlite.md) | draft | SQLite engine: honker-core/rusqlite mapping | OQ-05, OQ-06, OQ-09 |
-| [engine-postgres.md](engine-postgres.md) | draft | Postgres engine: tokio-postgres/LISTEN mapping | OQ-05, OQ-08, OQ-09 |
-| [queues.md](queues.md) | draft | Queue/scheduler/outbox semantics depth frame | OQ-05, OQ-09 |
+| [core-contract.md](core-contract.md) | draft | The unified trait surface, delivery guarantees, tx seam | OQ-08, OQ-10 |
+| [engine-sqlite.md](engine-sqlite.md) | draft | SQLite engine: honker-core/rusqlite mapping | OQ-05 (resolved), OQ-06, OQ-09 (resolved) |
+| [engine-postgres.md](engine-postgres.md) | draft | Postgres engine: tokio-postgres/LISTEN mapping | OQ-05 (resolved), OQ-08, OQ-09 (resolved) |
+| [queues.md](queues.md) | draft | Queue/scheduler/outbox semantics depth (resolved: ADR-009/ADR-010) | OQ-06 (rides) |
 | [deployment.md](deployment.md) | draft | Host semantics, connection budgets, knobs, matrix | OQ-08 |
 | [open-questions.md](open-questions.md) | draft | OQ tracker (promoted from OQ-ST register) | — |
 
@@ -43,29 +43,30 @@ pending architecture review and OQ resolution.
 | [006](decisions/006-wake-and-delivery-contract.md) | Wake contract — opaque wake + re-read; notify-vs-streams split | Accepted |
 | [007](decisions/007-transactional-seam.md) | Transactional seam — caller-held `TxHandle`, `*_tx` methods | Accepted |
 | [008](decisions/008-contract-v1-pinning.md) | Contract v1 surface pinning — surface partition, `TxHandle` shape, wake type, reserved strings, error taxonomy | Accepted |
+| [009](decisions/009-scheduler-collapse.md) | Scheduler collapse — queues + `schedule()`/`run_schedules`, `@every`-only v1, boundary guarantee row | Accepted |
+| [010](decisions/010-queue-semantics-depth.md) | Queue semantics depth — visibility/renewal, backoff curve, dead-letter, no-stranded-rows sweep, schema layout | Accepted |
 
 ## Open Questions
 
 Tracked in [open-questions.md](open-questions.md) (OQ-01..NN; the
 Phase 0 register's OQ-ST-01..08 promote one-to-one — OQ-NN mirrors
 OQ-ST-NN — with new Phase 1 questions appended after). Highlights,
-in suggested resolution order (OQ-04 resolved):
+in suggested resolution order (OQ-04, OQ-09, OQ-05 resolved):
 
-- ~~**OQ-04** (high): contract pinning — exact trait shape, handle
-  representation, error taxonomy, reserved strings, guarantee rows
-  for locks/scheduler~~ — **resolved** (2026-10-05,
-  [ADR-008](decisions/008-contract-v1-pinning.md); the scheduler
-  guarantee row transferred to OQ-09).
-- **OQ-05** (high): queue semantics depth — retry/backoff/dead-letter/
-  sweep design.
-- **OQ-09** (medium): scheduler as first-class mechanism vs queues +
-  `schedule()`; owns the scheduler guarantee row.
-- **OQ-06** (high): honker-core quality read — fork-trigger gate.
+- **OQ-06** (high): honker-core quality read — fork-trigger gate;
+  now carries two concrete fork candidates from the queue-depth
+  design (the no-stranded-rows sweep fix, dead-row `get_job`
+  visibility — complement vs fork is the read's call).
 - **OQ-08** (medium): capability-surface shape.
 - **OQ-10** (medium): contract versioning across engine crates.
 
-Resolved (Phase 0, kept with resolutions): OQ-01 (feature scope),
-OQ-02 (crate split), OQ-03 (drivers), OQ-07 (extension surface cut).
+Resolved (kept with resolutions): OQ-01 (feature scope), OQ-02
+(crate split), OQ-03 (drivers), OQ-07 (extension surface cut),
+~~OQ-04~~ (contract v1 pinning —
+[ADR-008](decisions/008-contract-v1-pinning.md)), ~~OQ-09~~
+(scheduler collapse — [ADR-009](decisions/009-scheduler-collapse.md);
+scheduler guarantee row pinned), ~~OQ-05~~ (queue semantics depth —
+[ADR-010](decisions/010-queue-semantics-depth.md)).
 
 No deferred OQs: all open questions are actionable Phase 1 work with
 complete evidence bases.