UK rowwise candidate: solve local and national targets as one matrix on the cloned spine (#762 PR A)

changelog.d/762-uk-rowwise-joint-solve.added.md

@@ -0,0 +1 @@
+Add a joint UK rowwise calibration solve for local, ladder, and national targets with receipted sampling, support, vintage, and incumbent-comparison evidence.

docs/gate-battery-contract.md

@@ -129,6 +129,7 @@ Canonical artifact keys:
 | `input_mass_reference` | the UK national build, when the licensed sidecar is supplied | `input_mass_parity` (UK override) |
 | `reviewed_input_mass_exclusions` (optional override) | the UK national build | `input_mass_parity` (UK override) |
 | `reviewed_qrf_tail_exclusions` (optional override) | the UK national build | `tail_concentration` (UK override) |
+| `uk_area_support_summary`, `exclusions_evaluated_on` | the UK local rowwise build | `area_support` (UK binding; reviewed exclusions carry measured shortfalls and stale entries fail) |
 
 The UK registry
 (`microcosm.build.uk_runtime.battery_bindings.UK_GATE_REGISTRY`) is the

docs/uk-local-cross-grain-reconciliation-802.md

@@ -10,7 +10,7 @@ the solve signature.
 ## Detection and bridges
 
 Exact matches use the measurement fields `concept`, `entity`, `map_to`, and
-`filters`. Two explicit UK bridges cover relationships that those fields
+`filters`. Explicit UK bridges cover relationships that those fields
 cannot express on their own:
 
 - The 10-cell `ons.household_composition.*` partition sums to the national
@@ -20,6 +20,16 @@ cannot express on their own:
   `dwp.uc.payment_distribution_*` rows also match the by-area target exactly
   and form a separate exhaustive national partition.
 
+Eight age bridges pair the single-cell UK controls
+`ons.population.age_0_9_by_region` through
+`ons.population.age_70_79_by_region` with the corresponding local
+`ons.age.0_10` through `ons.age.70_80` bands. They represent the same
+integer-age populations, but the national inclusive and local half-open filter
+encodings do not signature-match. Each bridge therefore rescales both the
+constituency and local-authority band to the `K02000001` UK total over the
+declared England, Wales, Scotland, and Northern Ireland legs. The national
+80--89 band has no local counterpart and is deliberately not bridged.
+
 These declarations live beside the UK Ledger target orchestration in
 `uk_runtime/ledger_targets.py`. Tests pin the precedence and complete bridge
 membership so a rule change requires an explicit doctrine-constants review.