ADR-013: fold the forked substrate into alkstore-sqlite — no fourth crate

Operator review of ADR-012's fork design re-litigated §1's crate
identity. alkstore-substrate misdescribed what the code is (unpublished,
path-dep-only, one consumer, SQLite-only — not a family-wide substrate);
the mechanical-diff hope was gone at fork time regardless (port deltas,
renames, re-derived half); and the alksocks F-1 lesson applies — a
vendored region under a second, weaker instruction set is a defect seam.
The fork folds into alkstore-sqlite as a bounded module subtree
(src/substrate/); ADR-012 §3–§6 retained verbatim, §2 retained with its
enforcement re-sited from the crate graph to diff fence + review +
contract-suite equivalence pins. OQ-11 item (1) dissolved.

docs/architecture/README.md

@@ -47,6 +47,7 @@ pending architecture review and OQ resolution.
 | [010](decisions/010-queue-semantics-depth.md) | Queue semantics depth — visibility/renewal, backoff curve, dead-letter, no-stranded-rows sweep, schema layout | Accepted |
 | [011](decisions/011-sqlite-substrate-fork.md) | SQLite substrate — fork honker-core into owned code | Accepted |
 | [012](decisions/012-forked-substrate-design.md) | Forked substrate design — contract-blind boundary, fidelity posture, port deltas | Accepted |
+| [013](decisions/013-fold-substrate-into-sqlite.md) | Fold the forked substrate into `alkstore-sqlite` — no fourth crate | Accepted |
 
 ## Open Questions
 
@@ -61,9 +62,9 @@ in suggested resolution order (OQ-04, OQ-09, OQ-05, OQ-06 resolved):
   honker-core's lineage, queue ops re-derived on contract v1.
 - **OQ-08** (medium): capability-surface shape.
 - **OQ-10** (medium): contract versioning across engine crates.
-- **OQ-11** (medium): forked-substrate follow-through (scaffold-time
-  decisions — [ADR-012](decisions/012-forked-substrate-design.md)'s
-  residue).
+- **OQ-11** (medium): forked-substrate follow-through (provenance
+  register format, cherry-pick procedure; item (1) dissolved by
+  [ADR-013](decisions/013-fold-substrate-into-sqlite.md)).
 
 Resolved (kept with resolutions): OQ-01 (feature scope), OQ-02
 (crate split), OQ-03 (drivers), OQ-07 (extension surface cut),