semantics: complete DEF-to-region migration, fix regressions

- Convert legacy [DEF🆔Type] anchors to #region/#endregion across 329 files
- Reinstate _normalize_timestamp_value in sql_generator.py
- Fix MarkerLogger→logger migration in events.py (molecular CoT markers)
- Fix dataset_review orchestrator dependencies (_build_execution_snapshot)
- Fix config_manager stale-record deletion (moved to save path only)
- Add 77 missing [/DEF:] closers in 5 unbalanced test files
- Update assistant_chat.integration.test.js for #region format
- Apply molecular-cot-logging markers (REASON/REFLECT/EXPLORE) via logger.* methods

backend/src/api/routes/__init__.py

@@ -1,9 +1,9 @@
 # #region ApiRoutesModule [C:3] [TYPE Module] [SEMANTICS routes, lazy-import, module-registry]
 # @BRIEF Provide lazy route module loading to avoid heavyweight imports during tests.
-# @LAYER API
-# @INVARIANT Only names listed in __all__ are importable via __getattr__.
+# @LAYER: API
 # @RELATION CALLS -> [ApiRoutesGetAttr]
 # @RELATION BINDS_TO -> [Route_Group_Contracts]
+# @INVARIANT: Only names listed in __all__ are importable via __getattr__.
 
 # #region Route_Group_Contracts [C:3] [TYPE Block]
 # @BRIEF Declare the canonical route-module registry used by lazy imports and app router inclusion.
@@ -41,9 +41,9 @@ __all__ = [
 
 # #region ApiRoutesGetAttr [C:3] [TYPE Function]
 # @BRIEF Lazily import route module by attribute name.
-# @PRE name is module candidate exposed in __all__.
-# @POST Returns imported submodule or raises AttributeError.
 # @RELATION DEPENDS_ON -> [ApiRoutesModule]
+# @PRE: name is module candidate exposed in __all__.
+# @POST: Returns imported submodule or raises AttributeError.
 def __getattr__(name):
     if name in __all__:
         import importlib