chore: migrate GRACE-Poly anchors to hierarchical dotted naming

Systematic rename of all semantic anchors (#region, [DEF], @RELATION)
across 1400+ files — backend Python, frontend Svelte/TS, specs, docs:
- Flat anchors become Namespace.Module.Entity
- @RELATION references updated to match new anchor paths
- Zero business logic changes

backend/tests/services/test_validation_service_crud.py

@@ -1,6 +1,6 @@
 # #region Test.ValidationTaskService.Crud [C:3] [TYPE Module] [SEMANTICS test,validation,crud,task,run]
 # @BRIEF Tests for validation_service.py — CRUD: get/list/delete tasks, trigger runs, run history, run detail.
-# @RELATION BINDS_TO -> [ValidationService]
+# @RELATION BINDS_TO -> [Services.ValidationService]
 
 from pathlib import Path
 import sys