feat: KI-Agent toggle button in Dokumenten-Pruefung

Green pill button: 'KI-Agent aus' / 'KI-Agent aktiv (1.874 MCs)'
Toggles use_agent flag which is passed through the full chain:
Frontend → DocCheckRequest → _run_doc_check → _check_single_document
→ check_document_with_controls(use_agent=True)
→ ComplianceAgent with tool calling

Default: OFF (deterministic regex). User can enable per scan.
Also works via env var COMPLIANCE_USE_AGENT=true for always-on.

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

admin-compliance/app/sdk/agent/_components/DocCheckTab.tsx

@@ -31,6 +31,7 @@ export function DocCheckTab() {
     try { const s = localStorage.getItem('doc-check-entries'); return s ? JSON.parse(s) : [newEntry()] } catch { return [newEntry()] }
   })
   const [checkCookieBanner, setCheckCookieBanner] = useState(false)
+  const [useAgent, setUseAgent] = useState(false)
   const [loading, setLoading] = useState(false)
   const [progress, setProgress] = useState('')
   const [results, setResults] = useState<any>(() => {
@@ -92,6 +93,7 @@ export function DocCheckTab() {
             url: e.url.trim(),
           })),
           check_cookie_banner: checkCookieBanner,
+          use_agent: useAgent,
         }),
       })
       if (!startRes.ok) throw new Error(`Pruefung konnte nicht gestartet werden: ${startRes.status}`)
@@ -192,6 +194,19 @@ export function DocCheckTab() {
           />
           Cookie-Banner pruefen
         </label>
+
+        <button
+          type="button"
+          onClick={() => setUseAgent(!useAgent)}
+          className={`flex items-center gap-2 px-3 py-1.5 rounded-full text-xs font-medium border transition-colors ${
+            useAgent
+              ? 'bg-emerald-100 border-emerald-300 text-emerald-800'
+              : 'bg-gray-50 border-gray-200 text-gray-500 hover:bg-gray-100'
+          }`}
+        >
+          <span className={`w-2 h-2 rounded-full ${useAgent ? 'bg-emerald-500' : 'bg-gray-300'}`} />
+          {useAgent ? 'KI-Agent aktiv (1.874 MCs)' : 'KI-Agent aus'}
+        </button>
       </div>
 
       {/* Submit */}