Add bounded GRB map acquisition

backend/app/providers/grb.py

@@ -9,12 +9,26 @@ class GRBProvider(BaseReferenceProvider):
             provider_name="grb",
             display_name="GRB",
             authority_level="authoritative",
-            supported_layers=["buildings", "roads", "parcels"],
+            supported_layers=["buildings", "roads", "water", "parcels"],
             supported_geometry_types=["Polygon", "MultiPolygon", "LineString", "MultiLineString"],
-            supported_query_modes=["area"],
-            fetch_signature="POST /api/v1/external/grb/fetch",
-            limitation_message="GRB live WFS/download integration is not configured in Sprint 7B.",
-            attribution="Digitaal Vlaanderen - Basiskaart Vlaanderen (GRB)",
-            license_note="Use must follow Digitaal Vlaanderen open data and attribution terms.",
-            configured=False,
+            supported_query_modes=["bbox", "persisted_area"],
+            fetch_signature="POST /api/v1/projects/{project_id}/datasets/grb/acquire",
+            limitation_message=(
+                "Alleen expliciet begrensde selecties tot 20 km per zijde worden opgehaald. "
+                "Volledige providerdownloads en onbeperkte queries zijn niet toegestaan."
+            ),
+            attribution="Bron: Grootschalig Referentie Bestand Vlaanderen, Digitaal Vlaanderen",
+            license_note="Hergebruik volgens de open-datavoorwaarden en bronvermelding van Digitaal Vlaanderen.",
+            configured=True,
         )
+
+    def fetch(self, project_id: str, area_id: str | None, layers: list[str]) -> dict:
+        del project_id, area_id, layers
+        return {
+            "provider": self.provider_name,
+            "status": "bounded_request_required",
+            "message": (
+                "Use POST /api/v1/projects/{project_id}/datasets/grb/acquire with an EPSG:4326 "
+                "bounding box and one governed product key."
+            ),
+        }

backend/app/providers/registry.py

@@ -78,11 +78,23 @@ class ExternalProviderRegistry:
         del project_id, area_id
         provider = self.get(provider_name)
         mapping = self.dataset_mapping(provider.provider_name, requested_dataset_role=requested_dataset_role)
-        if provider.provider_name in {"grb", "osm"}:
+        if provider.provider_name == "grb":
+            return ProviderImportResult(
+                provider_name="grb",
+                status="bounded_request_required",
+                message=(
+                    "Use the governed project GRB acquisition endpoint with an EPSG:4326 bounding box "
+                    "and one supported layer."
+                ),
+                requested_layers=layers,
+                dataset_role=mapping.dataset_role,
+                source_name=mapping.source_name,
+            )
+        if provider.provider_name == "osm":
             return ProviderImportResult(
                 provider_name=provider.provider_name,
                 status="not_configured",
-                message=f"No live {provider.display_name} import is configured in Sprint 7B.",
+                message=f"No live {provider.display_name} import is configured.",
                 requested_layers=layers,
                 dataset_role=mapping.dataset_role,
                 source_name=mapping.source_name,