feat: Art. 11 DSGVO — reject DSR when data subject not identifiable

- New DSRArt11Service: handles rejection with proper legal basis,
  automated email notification to requester explaining Art. 11
- POST /dsr/{id}/reject-art11 endpoint
- ActionButtons.tsx: "Nicht identifizierbar (Art. 11)" button
  shown when identity is not yet verified
- Also fixes: DSR export type-cast rollback handling

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

admin-compliance/app/sdk/dsr/[requestId]/_components/ActionButtons.tsx

@@ -9,7 +9,8 @@ export function ActionButtons({
   onExtendDeadline,
   onComplete,
   onReject,
-  onAssign
+  onAssign,
+  onRejectArt11,
 }: {
   request: DSRRequest
   onVerifyIdentity: () => void
@@ -17,6 +18,7 @@ export function ActionButtons({
   onComplete: () => void
   onReject: () => void
   onAssign: () => void
+  onRejectArt11?: () => void
 }) {
   const isTerminal = request.status === 'completed' || request.status === 'rejected' || request.status === 'cancelled'
 
@@ -48,12 +50,23 @@ export function ActionButtons({
   return (
     <div className="space-y-2">
       {!request.identityVerification.verified && (
-        <button
-          onClick={onVerifyIdentity}
-          className="w-full px-4 py-2 bg-yellow-500 text-white hover:bg-yellow-600 rounded-lg transition-colors text-sm font-medium"
-        >
-          Identitaet verifizieren
-        </button>
+        <>
+          <button
+            onClick={onVerifyIdentity}
+            className="w-full px-4 py-2 bg-yellow-500 text-white hover:bg-yellow-600 rounded-lg transition-colors text-sm font-medium"
+          >
+            Identitaet verifizieren
+          </button>
+          {onRejectArt11 && (
+            <button
+              onClick={onRejectArt11}
+              className="w-full px-4 py-2 text-gray-600 bg-gray-50 hover:bg-gray-100 border border-gray-200 rounded-lg transition-colors text-sm"
+              title="Person kann anhand der gespeicherten Daten nicht identifiziert werden (Art. 11 DSGVO)"
+            >
+              Nicht identifizierbar (Art. 11)
+            </button>
+          )}
+        </>
       )}
 
       <button