fix(mock-data): Fake-Daten bei leerer DB entfernt — ISMS 0%, Dashboard keine simulierten Trends, Compliance-Hub keine Fallback-Zahlen

- ISMS Overview: 14% → 0% bei leerer DB, "not_started" Status, alle Kapitel 0%
- Dashboard: 12-Monate simulierte Trend-Historie entfernt
- Compliance-Hub: Hardcoded Fallback-Statistiken (474/180/95/120/79/44/558/19) → 0
- SQLAlchemy Bug: `is not None` → `.isnot(None)` in SoA-Query
- Hardcoded chapter_7/8_status="pass" → berechnet aus Findings

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

admin-compliance/app/sdk/compliance-hub/page.tsx

@@ -365,7 +365,7 @@ export default function ComplianceHubPage() {
               </div>
               <div className="flex items-center gap-6 mb-4">
                 <div>
-                  <p className="text-4xl font-bold text-purple-600">{mappings?.total || 474}</p>
+                  <p className="text-4xl font-bold text-purple-600">{mappings?.total || 0}</p>
                   <p className="text-sm text-slate-500">Mappings gesamt</p>
                 </div>
                 <div className="flex-1 h-16 bg-slate-50 rounded-lg p-3">
@@ -377,19 +377,14 @@ export default function ComplianceHubPage() {
                       </span>
                     ))}
                     {!mappings?.by_regulation && (
-                      <>
-                        <span className="px-2 py-0.5 bg-purple-100 text-purple-700 rounded text-xs">GDPR: 180</span>
-                        <span className="px-2 py-0.5 bg-blue-100 text-blue-700 rounded text-xs">AI Act: 95</span>
-                        <span className="px-2 py-0.5 bg-green-100 text-green-700 rounded text-xs">BSI: 120</span>
-                        <span className="px-2 py-0.5 bg-orange-100 text-orange-700 rounded text-xs">CRA: 79</span>
-                      </>
+                      <span className="px-2 py-0.5 bg-slate-100 text-slate-500 rounded text-xs">Keine Mappings vorhanden</span>
                     )}
                   </div>
                 </div>
               </div>
               <p className="text-sm text-slate-600">
-                Automatisch generierte Verknuepfungen zwischen {dashboard?.total_controls || 44} Controls
-                und {dashboard?.total_requirements || 558} Anforderungen aus {dashboard?.total_regulations || 19} Verordnungen.
+                Automatisch generierte Verknuepfungen zwischen {dashboard?.total_controls || 0} Controls
+                und {dashboard?.total_requirements || 0} Anforderungen aus {dashboard?.total_regulations || 0} Verordnungen.
               </p>
             </div>