feat: add official Kempen operating scope

docs/DATASET_STRATEGY.md

@@ -88,6 +88,24 @@ Kempen reuses the same operator with an explicit approved boundary, project,
 area and scope key; an ambiguous regional label is never converted into an
 invented boundary.
 
+## Operational Kempen scope
+
+The canonical regional workspace uses the official 28-municipality Vlaamse
+`Vervoerregio Kempen` policy boundary. `scripts/geographic_scopes.py` is the
+operator source of truth for its members and current NIS codes. The resulting
+regional geometry is a union of current authoritative VRBG municipality
+boundaries.
+
+- Project: `Kempen Regional Workbench`.
+- Regional Area: `Vervoerregio Kempen - officiële operationele grens`.
+- Member Areas: one current official boundary for every municipality.
+- Scope key: `kempen-transport-region`.
+- Provenance: authority URL, VRBG request URL, member codes, fetch timestamp,
+  artifact checksums and the policy-boundary limitation.
+- Scale policy: thematic providers are partitioned and validated separately;
+  no interactive request or application startup may download the entire
+  region or silently substitute missing data.
+
 ## User-uploaded raster strategy
 V1 must support controlled local datasets because public raster access and model compatibility can be difficult.