commerce: reconciliation queries + federated-catalog stub (32 tests) — Phase 4 done

recon.sx — reconciliation as relational queries over the ledger: per-order
summary tuples + recon-statuso/neto/mismatcho miniKanren relations, so
overpaid/underpaid/settled and "settled to net N" are backward run* queries.
Tests cover double-charge guard, partial refund, webhook replay.

federation.sx (out-of-scope stub) — a federated catalog is the union of each
instance's product facts, so the same relations query cross-instance
(instances-with-sku, sku-offers, cheapest-offer). In-process mock, no network.

Completes the commerce-on-sx roadmap (Phases 1-4). Total 185/185 across 11 suites.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

plans/commerce-on-sx.md

@@ -21,7 +21,7 @@ reconciliation — all auditable via the event log.
 
 ## Status (rolling)
 
-`bash lib/commerce/conformance.sh` → **153/153** (9 suites: catalog, cart, price, api, promo, stack, quote, ledger, order) — Phases 1-3 done
+`bash lib/commerce/conformance.sh` → **185/185** (11 suites: catalog, cart, price, api, promo, stack, quote, ledger, order, recon, federation) — **Phases 1-4 done (roadmap complete)**
 
 ## Ground rules
 
@@ -71,11 +71,24 @@ lib/commerce/api.sx ── (commerce/add) (commerce/total) (commerce/checkout)
 - [x] order ledger as a `persist` stream; idempotent reconciliation
 
 ## Phase 4 — Reconciliation + federation
-- [ ] mismatch detection (paid≠ordered) as queries over the ledger
-- [ ] cross-instance catalog (federated marketplace) — out-of-scope stub
-- [ ] tests: webhook replay, partial refund, double-charge guard
+- [x] mismatch detection (paid≠ordered) as queries over the ledger
+- [x] cross-instance catalog (federated marketplace) — out-of-scope stub
+- [x] tests: webhook replay, partial refund, double-charge guard
 
 ## Progress log
+- 2026-06-07 — `recon.sx` + `federation.sx` (**Phase 4 complete — roadmap done**).
+  `recon.sx`: reconciliation as relational queries over the ledger. Per-order
+  summary tuples (id total paid refunded net status); `recon-statuso`/`neto`/
+  `mismatcho` are miniKanren relations, so "which orders are overpaid?",
+  "settled to net N?" are backward `run*` queries. Helpers: overpaid/underpaid/
+  settled/unpaid-orders, mismatched-orders, orders-with-net, ledger-discrepancy.
+  Tests cover double-charge guard (two refs → :overpaid), partial refund (net <
+  total → :underpaid), webhook replay (same ref twice → single :paid, :ok). 20/20.
+  `federation.sx` (out-of-scope stub): a federated catalog is the UNION of each
+  instance's product facts, so the SAME relations query cross-instance —
+  `fed-producto`/`fed-priceo`, `instances-with-sku`, `sku-offers`, deterministic
+  `cheapest-offer`. In-process mock, no real network/ActivityPub. 12/12.
+  Total 185/185 across 11 suites.
 - 2026-06-07 — `order.sx` (**Phase 3 complete**, checkboxes 1-2): order lifecycle
   as a flow-on-sx flow `(lambda (oid) (begin (request 'reserve oid) (request
   'payment oid) (request 'fulfil oid)))` — pure orchestration carrying only the