Add Belgium and North Sea coverage foundation

docs/API_CONTRACTS.md

@@ -935,6 +935,49 @@ Read simplified job status payload.
 
 ## Provider registry
 
+The legacy Sprint 7 provider registry remains the exact
+`grb|osm|manual|fixture` import abstraction. National and maritime source
+authority is exposed separately so adding official source families cannot
+silently change that import contract.
+
+### GET `/api/v1/external/coverage/catalog`
+
+Returns the normalized Belgium and Belgian North Sea theme vocabulary, legal
+coverage zones, allowed availability states and audited source contracts.
+Every source includes authority, native layers, geometry types, acquisition
+mode, source URL, attribution, licence and limitation text.
+
+Allowed result states are exactly:
+
+- `operational`: a matching `ready` Dataset is materialized in the project;
+- `partial`: the governed integration exists but matching project data is
+  absent or incomplete;
+- `not_configured`: an audited source has no operational adapter;
+- `unsupported`: no audited contract supports the theme in that zone.
+
+### POST `/api/v1/external/coverage/resolve`
+
+Resolves a user-drawn EPSG:4326 bbox against persisted national and maritime
+Areas. Cross-region and land/sea selections remain split by zone.
+
+```json
+{
+  "project_id": "uuid",
+  "bbox": {
+    "minx": 2.65,
+    "miny": 51.05,
+    "maxx": 2.85,
+    "maxy": 51.20
+  },
+  "themes": ["buildings", "surface_water", "bathymetry"]
+}
+```
+
+The response returns `intersected_zones`, `outside_supported_scope`, one item
+per zone/theme combination, matching source names and IDs of actually
+materialized Datasets. An empty `themes` list requests the complete normalized
+vocabulary. Unknown themes fail with `COVERAGE_THEME_UNSUPPORTED`.
+
 ### GET `/api/v1/external/providers`
 
 Returns all configured provider capability descriptors.

docs/CODEX_EXECUTION_LOG.md

@@ -1,5 +1,31 @@
 ## Autonomous RC program for Belgium and the Belgian North Sea (2026-07-17)
 
+### RC-4 national and maritime coverage foundation
+
+- Added an independent coverage registry so the exact Sprint 7
+  `grb|osm|manual|fixture` provider contract remains unchanged.
+- Added `GET /api/v1/external/coverage/catalog` and
+  `POST /api/v1/external/coverage/resolve` with canonical envelopes, normalized
+  themes and explicit project-materialization checks.
+- Added `provision_belgium_north_sea_scope.py`. It accepts only the official
+  NGI AdminVector archive, RBINS marine reporting units and the exact 15-layer
+  `imsp26` WFS allowlist. It verifies archive/response limits, safe extraction,
+  layer counts, pagination, geometries and SHA256 evidence.
+- Verified live source contracts from the Codex host: all 15 MSP layers were
+  reachable and returned 101 features in total; the current RBINS reporting
+  units yielded BPNS, territorial sea, EEZ and continental-shelf geometries.
+- The territorial sea is derived only by unioning official 0-1 nm and 1-12 nm
+  units. EEZ and continental shelf retain the same official offshore geometry
+  as separate records with different legal-domain provenance.
+- Frontend startup now prefers a materialized
+  `Belgium and North Sea Workbench`; drawn bboxes receive a compact,
+  zone-split coverage matrix. Existing Mol/Kempen workspaces remain available.
+- Local validation passed 986 backend tests, frontend typecheck/build, the
+  full readiness gate, Alembic head `202607160001`, complete offline migration
+  SQL and live-smoke shell syntax.
+- Tower fetch-only, persistence, live coverage API and browser acceptance are
+  the remaining RC-4 exit evidence.
+
 - Froze the RC geography as all Belgian land plus the separately labelled
   territorial sea, EEZ and continental shelf.
 - Retained Mol and the Kempen as validated regression areas instead of the

docs/DATA_SOURCES.md

@@ -719,6 +719,42 @@ the canonical vector persistence path for Mol and Kempen. Additional Flemish
 vector themes still require governed regional operators; a catalogue record
 alone never makes them operational.
 
+## Belgium and Belgian North Sea scope foundation
+
+The release-candidate workbench uses two distinct registries:
+
+- the fixed Sprint 7 import-provider registry for `grb`, `osm`, `manual` and
+  `fixture`;
+- the national coverage registry for audited source authority and actual
+  project materialization by theme and zone.
+
+The explicit operator
+`scripts/provision_belgium_north_sea_scope.py` downloads the official NGI
+AdminVector EPSG:4326 GeoPackage archive, verifies size and archive safety,
+requires the territory, maritime zone, region, province and municipality
+layers, and retains archive/GeoPackage/artifact checksums. NGI output is
+licensed CC BY 4.0 and persists as reference Datasets through
+`DatasetService`.
+
+The same operator obtains the RBINS/BMDC
+`od_nature:marine_reporting_units_2024` WFS layer. The territorial sea is the
+union of official 0-1 nm coastal waters and 1-12 nm territorial waters. The
+official offshore-beyond-12-nm geometry is persisted twice only to preserve
+the distinct legal semantics of the EEZ water column and continental-shelf
+seabed/subsoil. This is explicit provenance-preserving derivation, not
+invented geometry.
+
+The legally current Belgian Marine Spatial Plan 2026-2034 is fetched from the
+fixed `imsp26` WFS allowlist and retained as one versioned reference Dataset.
+No live vessel activity, depth, water volume or other unsupported metric is
+inferred from these plan zones.
+
+The coverage resolver reports a theme `operational` only when a matching
+`ready` Dataset exists in the selected project. Implemented acquisition
+without project materialization is `partial`; Walloon, Brussels, Statbel and
+MDK families remain `not_configured` until their own bounded adapters and
+source-specific metric contracts are implemented.
+
 ## Bathymetry, inland profiles and maritime scope
 
 The official VHA Digital Atlas profile-point layer is the first operational

docs/DATA_SPECIFICATION.md

@@ -369,6 +369,31 @@ Ondersteund:
 - GPKG
 - WFS-resultaten
 
+### National and maritime coverage contracts
+
+Belgium-wide and maritime reference Datasets use the same Dataset and
+VectorFeature entities as every other vector source. No parallel national
+schema is introduced.
+
+Required source metadata includes:
+
+```yaml
+authority_level: authoritative|official_context|contextual
+coverage_zones:
+  - belgium|flanders|wallonia|brussels
+  - belgian_north_sea|territorial_sea|exclusive_economic_zone|continental_shelf
+source_url: https://...
+attribution: text
+license_note: text
+reference_layer_name: normalized_layer_key
+```
+
+EEZ and continental-shelf records may have equal horizontal geometry while
+their `legal_domain` differs. They must remain distinct records. A selected
+bbox crossing regions or the coast produces zone-specific coverage items;
+only metrics with compatible source meaning, unit, time and method may be
+merged.
+
 Metadata:
 
 - CRS

docs/RC_ROADMAP_BELGIUM_NORTH_SEA.md

@@ -291,6 +291,11 @@ errors.
 
 ## RC-4 - Belgium and North Sea coverage foundation
 
+**State: in progress.** The national coverage registry, canonical
+catalog/resolve API, explicit NGI/RBINS operator, frontend selection matrix and
+focused safety tests are implemented. Local readiness is green. Tower
+fetch-only, persistence, live API and browser acceptance remain the phase exit.
+
 ### Work
 
 1. Persist NGI authoritative Belgium land and administrative scopes.

docs/STORAGE_ARCHITECTURE.md

@@ -43,8 +43,28 @@ storage/
     osm/
     sentinel/
     dhmv/
+  operator-data/
+    geographic-scopes/
+      belgium-north-sea/
+        adminvector_4326.zip
+        adminvector/
+          adminvector_4326.gpkg
+        belgium_land_boundary.geojson
+        belgium_regions.geojson
+        belgium_provinces.geojson
+        belgium_municipalities.geojson
+        ngi_maritime_zone.geojson
+        marine_legal_scopes.geojson
+        marine_spatial_plan_2026.geojson
+        manifest.json
 ```
 
+The Belgium/North Sea directory is written only by the explicit
+`provision_belgium_north_sea_scope.py` operator. The manifest binds every
+artifact to SHA256, source URL, edition/validity and feature count. Persistence
+still runs through the ordinary Dataset upload API; operator artifacts are
+evidence and replay inputs, not an alternate database.
+
 ## Upload policy
 
 When a file is uploaded:

docs/TODO.md

@@ -14,6 +14,12 @@ maritieme zones.
 - [x] RC-2: liveness/readiness/capabilities fail-closed en waarheidsgetrouw maken.
 - [x] RC-2: verweesde jobs en analysis runs na een procesherstart verzoenen.
 - [x] RC-3: expliciete rasterkeuze en temporeel compatibele detectie-QA afdwingen.
+- [x] RC-4: aparte nationale bron- en dekkingscontracten implementeren zonder
+  het vaste Sprint 7-providerregister te wijzigen.
+- [x] RC-4: expliciete NGI/RBINS-operator en selectiegebonden coverage-API
+  implementeren en lokaal valideren.
+- [ ] RC-4: Tower fetch-only, canonieke persistence en live browseracceptatie
+  bewijzen.
 - [ ] RC-4: nationale basisdekking, Wallonie, Brussel en Belgische Noordzee via
   beheerde providers en golden areas operationaliseren.
 - [ ] RC-5: secrets/configuratie/uploadlimieten/immutable deploy en rollback