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/test_models_clean_release_ext.py

@@ -3,7 +3,7 @@
 #        CleanProfilePolicy, ComplianceCheckRun, ReleaseCandidate, DistributionManifest,
 #        ComplianceRun, ComplianceViolation, ComplianceReport, ApprovalDecision, PublicationRecord,
 #        CleanReleaseAuditLog, SourceRegistrySnapshot, CleanPolicySnapshot, ComplianceStageRun.
-# @RELATION BINDS_TO -> [CleanReleaseModels]
+# @RELATION BINDS_TO -> [Models.CleanRelease.CleanReleaseModels]
 
 from datetime import datetime, timezone
 import pytest