Add governed SPW bathymetry analysis

docs/CODEX_EXECUTION_LOG.md

@@ -2,6 +2,28 @@
 
 ### Post-RC national data federation (2026-07-19)
 
+- Continued the national federation pass with official history and
+  bathymetry. Statbel's real 2021 geometry release exposed two documented
+  packaging differences: the ZIP member omits the repeated `31370` token and
+  `dt_situation` uses `YYYY/MM/DD`. The preflight now normalizes only those
+  forms and retains every existing fail-closed content check.
+- The corrected Tower fetch-only pass validated national 2021-2024 snapshots,
+  each with 19,795 retained sector geometries, before any API persistence.
+- Downloaded the fixed official SPW Geoportail bathymetry release
+  (`0a544b42-0b30-4c8e-85e7-38149b99eae0`) to persistent operator evidence.
+  SHA-256 is
+  `04122a1c5cecc7b77be025b580995d024545e82d8310e158b4c112f7fa5f8a6e`.
+  GDAL verified a 456,893 by 179,437 Float32 EPSG:3812 source at 0.5 m,
+  nodata `-9999`, with mDNG waterbed elevations.
+- Added `import_spw_bathymetry.py`, bounded COG persistence, source-specific
+  coverage resolution, raster selection/image APIs and frontend Waterbodem
+  integration. The contract exposes bed elevation, measured-cell hectares and
+  coverage only; current depth, volume and datum conversion remain blocked.
+- Added the bathymetry PNG route to the explicit non-envelope API audit set
+  after the first full gate correctly rejected its untracked binary response.
+- The complete repository gate passed 1,052 backend tests, 22 frontend tests,
+  frontend typecheck/build, one Alembic head and all readiness checks before
+  live deployment.
 - Added explicit administrative and maritime themes for persisted NGI/RBINS
   reference data and made readiness depend on analyzable themes rather than a
   raw Dataset count.