feat(controls): Zitierfaehigkeit — Embedding-Re-Link + Atom-Vererbung

citation_backfill Tier-1 von totem sha256-Hash auf Semantik-Suche gegen die
re-ingestierten, article_label-tragenden Chunks umgestellt (Fundstelle aus
article_label); rag_client reicht article_label durch (additiv, Default-Feld).
NEU: scripts/atom_citation_inheritance.py vererbt source_citation parent->atom
(license_rule != 3), iterativ. macmini-Apply verifiziert: Zitierfaehigkeit
6.9%->61.3% (+171.765 Atome), Stichprobe korrekt (Atom == Parent-Fundstelle).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

control-pipeline/services/rag_client.py

@@ -33,6 +33,7 @@ class RAGSearchResult:
     paragraph: str
     source_url: str
     score: float
+    article_label: str = ""
     collection: str = ""
     page: Optional[int] = None
 
@@ -90,6 +91,7 @@ class ComplianceRAGClient:
                     regulation_short=r.get("regulation_short", ""),
                     category=r.get("category", ""),
                     article=r.get("article", ""),
+                    article_label=r.get("article_label", ""),
                     paragraph=r.get("paragraph", ""),
                     source_url=r.get("source_url", ""),
                     score=r.get("score", 0.0),
@@ -171,6 +173,7 @@ class ComplianceRAGClient:
                     regulation_short=r.get("regulation_short", ""),
                     category=r.get("category", ""),
                     article=r.get("article", ""),
+                    article_label=r.get("article_label", ""),
                     paragraph=r.get("paragraph", ""),
                     source_url=r.get("source_url", ""),
                     score=0.0,