feat: RAG Chunk Browser — alle Collections + 59 EDPB/WP29/DSFA Eintraege

- rag-constants.ts: 11 → 59 EDPB/WP29/EDPS + 20 DSFA Muss-Listen
- ChunkBrowserQA: Dropdown von 3 auf 7 Collections erweitert
  (+ bp_dsfa_corpus, bp_compliance_recht, bp_legal_templates, bp_nibis_eh)
- page.tsx: Collection-Totals aktualisiert (datenschutz 17459, dsfa 8666)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

admin-lehrer/app/(admin)/ai/rag/components/ChunkBrowserQA.tsx

@@ -32,6 +32,10 @@ const COLLECTIONS = [
   'bp_compliance_gesetze',
   'bp_compliance_ce',
   'bp_compliance_datenschutz',
+  'bp_dsfa_corpus',
+  'bp_compliance_recht',
+  'bp_legal_templates',
+  'bp_nibis_eh',
 ]
 
 export function ChunkBrowserQA({ apiProxy }: ChunkBrowserQAProps) {