feat: add governed hydrology and historical imagery

docs/CODEX_EXECUTION_LOG.md

@@ -8438,3 +8438,33 @@ Next:
 - Integrate Waterinfo/VMM station observations as point time series and add
   historical orthophoto acquisition, while preserving their spatial and
   methodological limitations.
+
+## Sprint 203 - Governed Waterinfo history and historical orthophotos (2026-07-15)
+
+Implemented:
+- Added `provision_waterinfo_station_history.py` using the documented Waterinfo
+  KiWIS annual water-level/discharge groups. The operator filters station
+  points against the exact persisted Area, retains raw JSON plus SHA256
+  manifests and writes only through the canonical upload API.
+- Persisted one Point Dataset per station/year and kept station identities in
+  separate temporal series. Added backend `mean` aggregation without combining
+  stations or inferring area-wide water level/volume.
+- Added a governed orthophoto allowlist for the most-recent product, annual
+  winter mosaics 2012-2025, older winter periods, RGB 1979-1990 and
+  panchromatic 1971. Arbitrary WMS URLs/layers remain impossible.
+- Added raster temporal metadata and a constrained PNG rendering endpoint for
+  persisted orthophoto datasets. The map can select and display official
+  historical imagery over the same bounded rectangle.
+- Historical products explicitly bypass configured-YOLO and current-GRB QA;
+  only `most_recent` retains that path.
+- Updated source inventory behavior and wrote a governed source backlog with
+  acceptance criteria for BWK/Natura 2000, agricultural parcels, Buildings
+  Register, DHMV and bathymetry.
+
+Validation evidence:
+- Focused Waterinfo/orthophoto/semantic metric tests and frontend typecheck/build
+  passed before the full repository gate.
+
+Remaining operational step:
+- Deploy the all-in-one image, provision the real Mol Waterinfo station series
+  and verify one historical image acquisition/overlay through the LAN browser.