docs: resolve OQ-04 — contract v1 pinned (ADR-008): surface partition, TxHandle-on-handle-trait, Wake/WakeReceiver, reserved __alkstore_ namespace, error taxonomy, engine-crate constructors, locks guarantee row

docs/architecture/overview.md

@@ -1,6 +1,6 @@
 ---
 status: draft
-last_updated: 2026-10-04
+last_updated: 2026-10-05
 ---
 
 # alkstore — Overview
@@ -28,7 +28,7 @@ Per [ADR-001](decisions/001-crate-split.md):
 
 | Crate | Contents | Driver dependencies |
 |---|---|---|
-| `alkstore` (core) | trait surface, types, error model, capability flags | none |
+| `alkstore` (core) | trait surface, types, error model | none (capability flags, if ever, are OQ-08's to add) |
 | `alkstore-sqlite` | SQLite engine ([ADR-003](decisions/003-sqlite-driver.md)) | rusqlite, honker-core |
 | `alkstore-postgres` | Postgres engine ([ADR-004](decisions/004-postgres-driver.md)) | tokio-postgres, deadpool-postgres |
 | (mem engine, optional) | test convenience, decided at implementation ([ADR-001](decisions/001-crate-split.md)) | none |
@@ -71,6 +71,7 @@ Per [ADR-002](decisions/002-feature-scope.md):
 | [005](decisions/005-dependency-ownership.md) | Published libraries by default, named fork triggers | Accepted |
 | [006](decisions/006-wake-and-delivery-contract.md) | Opaque wake + re-read; notify-vs-streams guarantee split | Accepted |
 | [007](decisions/007-transactional-seam.md) | Caller-held `TxHandle` with `*_tx` methods | Accepted |
+| [008](decisions/008-contract-v1-pinning.md) | Contract v1 surface pinning (partition, TxHandle shape, wake type, reserved strings, error taxonomy) | Accepted |
 
 ## Non-goals