[split-required] Split 500-1000 LOC files across all services

backend-lehrer (5 files):
- alerts_agent/db/repository.py (992 → 5), abitur_docs_api.py (956 → 3)
- teacher_dashboard_api.py (951 → 3), services/pdf_service.py (916 → 3)
- mail/mail_db.py (987 → 6)

klausur-service (5 files):
- legal_templates_ingestion.py (942 → 3), ocr_pipeline_postprocess.py (929 → 4)
- ocr_pipeline_words.py (876 → 3), ocr_pipeline_ocr_merge.py (616 → 2)
- KorrekturPage.tsx (956 → 6)

website (5 pages):
- mail (985 → 9), edu-search (958 → 8), mac-mini (950 → 7)
- ocr-labeling (946 → 7), audit-workspace (871 → 4)

studio-v2 (5 files + 1 deleted):
- page.tsx (946 → 5), MessagesContext.tsx (925 → 4)
- korrektur (914 → 6), worksheet-cleanup (899 → 6)
- useVocabWorksheet.ts (888 → 3)
- Deleted dead page-original.tsx (934 LOC)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

website/app/admin/edu-search/_components/RulesTab.tsx

@@ -0,0 +1,37 @@
+'use client'
+
+export default function RulesTab() {
+  return (
+    <div className="space-y-6">
+      <div className="bg-amber-50 border border-amber-200 rounded-lg p-4">
+        <div className="flex items-start gap-3">
+          <span className="text-2xl">⚠️</span>
+          <div>
+            <h4 className="font-semibold text-amber-800">Tagging-Regeln Editor</h4>
+            <p className="text-sm text-amber-700">
+              Die Tagging-Regeln werden aktuell über YAML-Dateien verwaltet.
+              Ein visueller Editor ist in Entwicklung.
+            </p>
+          </div>
+        </div>
+      </div>
+
+      <div className="grid md:grid-cols-2 gap-6">
+        {[
+          { name: 'Doc-Type Regeln', file: 'doc_type_rules.yaml', desc: 'Klassifiziert Dokumente (Lehrplan, Arbeitsblatt, etc.)' },
+          { name: 'Fach-Regeln', file: 'subject_rules.yaml', desc: 'Erkennt Unterrichtsfächer' },
+          { name: 'Schulstufen-Regeln', file: 'level_rules.yaml', desc: 'Erkennt Primar, SekI, SekII, etc.' },
+          { name: 'Trust-Score Regeln', file: 'trust_rules.yaml', desc: 'Domain-basierte Vertrauensbewertung' },
+        ].map(rule => (
+          <div key={rule.file} className="bg-white border border-slate-200 rounded-lg p-6">
+            <h4 className="font-semibold text-slate-900 mb-2">{rule.name}</h4>
+            <p className="text-sm text-slate-500 mb-4">{rule.desc}</p>
+            <code className="text-xs bg-slate-100 px-2 py-1 rounded text-slate-600">
+              /rules/{rule.file}
+            </code>
+          </div>
+        ))}
+      </div>
+    </div>
+  )
+}