feat: add governed hydrology and historical imagery

docs/TODO.md

@@ -22,12 +22,55 @@
 - [x] Add a source inventory that separates loaded data from audited official follow-up sources.
 - [x] Add a local Ollama question window grounded in persisted GeoIntel metrics and installed server models.
 - [ ] Add a governed depth/bathymetry source before exposing water volume; never infer volume from 2D GRB water geometry.
-- [ ] Integrate one governed hydrology source (Waterinfo/VMM station series) without presenting point measurements as area-wide water volume.
-- [ ] Add bounded historical orthophoto acquisition and visual change analysis after validating layer/year coverage.
+- [x] Integrate governed Waterinfo/VMM annual station series without presenting point measurements as area-wide water volume.
+- [x] Add bounded historical orthophoto acquisition for official 1971-2025 products with a map overlay and no current-GRB QA on old imagery.
 - [ ] Add BWK/Natura 2000 and annual agricultural-use parcels through explicit provider/operator contracts.
 - [ ] Extend the official 1778/1873/1969 historical buildings, water and roads series from Mol to the approved regional scope with partitioned source audits.
 - [x] Connect a drawn rectangle to bounded official orthophoto acquisition, local configured-YOLO detection and persisted GRB QA.
 
+## Governed source expansion backlog
+
+Implement these in order. Every source must use an explicit operator/provider
+contract, retain raw checksummed evidence, persist through DatasetService and
+pass live Mol validation before regional expansion.
+
+### P1 - Biologische Waarderingskaart / Natura 2000
+
+- [ ] Confirm the official downloadable service/layer/version and licence for the 2025 state.
+- [ ] Define stable habitat/biotope/value fields and keep BWK valuation separate from Natura 2000 habitat classification.
+- [ ] Clip in EPSG:31370 to Mol, transform to EPSG:4326 and persist valid polygonal `vector_features` with source feature ids.
+- [ ] Add hectare metrics per governed class plus unknown/unmapped-class diagnostics; do not invent an annual trend from one state.
+- [ ] Add source manifest, unit tests, live row/count/geometry audit and map/source-inventory presentation.
+
+### P2 - Annual agricultural-use parcels
+
+- [ ] Inventory official annual editions and document schema/code-list changes before selecting a comparable year range.
+- [ ] Retain annual source files and crop code lists; normalize only fields whose meaning is stable across editions.
+- [ ] Persist separate annual Datasets with hectares by crop/use class and an explicit unstable-parcel-identity limitation.
+- [ ] Compare area/category totals over time; do not claim parcel lineage where identifiers or boundaries changed.
+- [ ] Validate Mol first, then partition all 28 Kempen municipalities with completeness/checksum manifests.
+
+### P3 - Buildings and Addresses Register
+
+- [ ] Define a governed snapshot operator and relation mapping between building unit, building object, address and GRB geometry.
+- [ ] Keep register lifecycle/status semantics separate from GRB footprint geometry and document match confidence/unmatched rows.
+- [ ] Add current building-status/address metrics without exposing personal data or treating addresses as households/population.
+- [ ] Add Mol reconciliation tests and a live mismatch report before regional import.
+
+### P4 - Digitaal Hoogtemodel Vlaanderen
+
+- [ ] Select official DTM/DSM product, service and native resolution; retain acquisition date and vertical reference.
+- [ ] Add bounded raster acquisition/clip storage with nodata, CRS, resolution and checksum validation.
+- [ ] Implement governed elevation, relief and slope statistics in metres/degrees; keep drainage interpretation explicitly derived.
+- [ ] Do not label terrain/surface height as water depth and do not enable volume from DHMV alone.
+
+### P5 - Water depth / bathymetry
+
+- [ ] Identify an authoritative source with compatible spatial coverage, vertical datum, date and uncertainty; otherwise keep volume unavailable.
+- [ ] Define waterbody linkage, surface elevation, bottom elevation and uncertainty propagation before adding any volume metric.
+- [ ] Validate coverage gaps and prohibit extrapolation outside measured/profiled waterbodies.
+- [ ] Add independent GIS review and golden-volume fixtures before exposing the result to users or Ollama.
+
 This file now starts with the current implementation status. Older preparation/backlog sections are preserved below as historical planning context and should not be treated as the live sprint board without checking `docs/CODEX_EXECUTION_LOG.md`.
 
 ## Release hardening status