Add governed Statbel edition probe

docs/CODEX_EXECUTION_LOG.md

@@ -1,3 +1,38 @@
+## Sprint 226 - Governed Statbel population edition probe (2026-07-16)
+
+Implemented:
+- Extended the explicit source-catalog audit with the official Statbel DCAT
+  Turtle catalog. The parser selects one latest Dutch population-by-sector
+  release and requires consistent period evidence, identifier, canonical
+  landing page, CC BY 4.0 license and allowlisted distribution identities.
+- Added strict endpoint and final-redirect validation plus a separate 5 MiB
+  response limit. The catalog probe never follows a ZIP/XLSX link, imports a
+  Dataset, writes PostGIS or enables background polling.
+- Kept population reference year, sector-geometry edition and REDEGEO layout
+  distinct. The 2025 NEW distribution is current; OLD is transition evidence,
+  and the separate 2026 sector geometry is not presented as 2026 population.
+- Reused the canonical source-catalog response, cache, operator CLI and Status
+  UI. Propagated the fixed URL and size bound through local, Compose and Unraid
+  configuration and added RDFLib as a pure-Python core parser dependency.
+
+Validation:
+- The bounded parser read the live official DCAT catalog and identified
+  `NodeID6475`, population edition `2025`, four distributions, the new REDEGEO
+  layout, legacy transition availability, CC BY 4.0 and catalog date
+  `2026-07-07` without requesting a distribution.
+- All 24 focused source-catalog tests passed, including hostile host, redirect,
+  configured URL, duplicate release, conflicting year, missing license,
+  missing current distribution and oversized-response failures.
+- Complete readiness passed with 801 backend tests, 110 documented routes, one
+  Alembic head, frontend typecheck and production build. Static Alembic SQL,
+  Ruff, diff checks and shell syntax also passed. Local Docker validation was
+  unavailable on Windows and is completed through the Tower deployment gate.
+
+Boundary:
+- This is publication evidence only. A future population edition still needs
+  a governed schema, sector-geometry and totals review before the existing
+  operator may create a new immutable Dataset.
+
 ## Sprint 225 - Governed ALZ edition probe (2026-07-16)
 
 Implemented: