feat(agent): Cookie-Result-View + Check-Historie aus Snapshots

Snapshot-getriebene Result-Views, entkoppelt vom Live-Check:
- CookieResultView: laedt cmp_vendors aus einem Snapshot (kein Re-Crawl),
  KPIs (Anbieter/Cookies/Marketing/Drittland) + Empfaenger-Gruppen
  (Eigene/AVV/Joint-Controller) + aufklappbare Vendor->Cookie-Tabelle.
- Historie (/sdk/agent/snapshots): alle gespeicherten Checks, jederzeit
  oeffnbar (DSB/Mitarbeiter) + Detail-Seite je Snapshot.
- Next.js-Proxys fuer GET /snapshots (Liste) + /snapshots/{id} (einzeln).

BMW-Snapshot 4603d15b: 83 Vendors / 780 Cookies. Library-Abgleich
(cookie_knowledge_db.lookup_cookie) folgt als Phase B.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

admin-compliance/app/sdk/agent/snapshots/page.tsx

@@ -0,0 +1,71 @@
+'use client'
+
+/**
+ * Check-Historie — listet gespeicherte Snapshots (alle Sites/Module).
+ * Ein DSB/Mitarbeiter kann jeden früheren Check öffnen, ohne neuen Check
+ * zu starten. Daten kommen aus den Snapshot-Rohdaten.
+ */
+
+import React, { useEffect, useState } from 'react'
+import Link from 'next/link'
+
+interface SnapMeta {
+  id: string
+  check_id?: string
+  site_domain?: string
+  site_label?: string
+  created_at?: string
+  replay_count?: number
+}
+
+export default function SnapshotHistory() {
+  const [snaps, setSnaps] = useState<SnapMeta[]>([])
+  const [loading, setLoading] = useState(true)
+
+  useEffect(() => {
+    let cancelled = false
+    fetch('/api/sdk/v1/agent/snapshots?limit=50')
+      .then(r => r.json())
+      .then(d => { if (!cancelled) setSnaps(d.snapshots || []) })
+      .catch(() => { if (!cancelled) setSnaps([]) })
+      .finally(() => { if (!cancelled) setLoading(false) })
+    return () => { cancelled = true }
+  }, [])
+
+  return (
+    <div className="p-6 max-w-4xl space-y-4">
+      <div>
+        <h1 className="text-xl font-semibold text-gray-900">Check-Historie</h1>
+        <p className="text-xs text-gray-500 mt-1">
+          Frühere Compliance-Checks aus gespeicherten Snapshots — jederzeit
+          ansehbar, ohne neuen Check zu starten.
+        </p>
+      </div>
+
+      {loading ? (
+        <div className="text-sm text-gray-500">Lade Historie…</div>
+      ) : snaps.length === 0 ? (
+        <div className="text-sm text-gray-400">Keine gespeicherten Checks gefunden.</div>
+      ) : (
+        <div className="border rounded-lg divide-y divide-gray-100">
+          {snaps.map(s => (
+            <Link
+              key={s.id}
+              href={`/sdk/agent/snapshots/${s.id}`}
+              className="flex items-center gap-3 px-4 py-3 hover:bg-gray-50 text-sm"
+            >
+              <span className="font-medium text-gray-800 w-44 truncate">
+                {s.site_label || s.site_domain || 'unbekannt'}
+              </span>
+              <span className="text-gray-500 flex-1 min-w-0 truncate">{s.site_domain}</span>
+              <span className="text-xs text-gray-400 whitespace-nowrap">
+                {(s.created_at || '').slice(0, 16).replace('T', ' ')}
+              </span>
+              <span className="text-gray-300">›</span>
+            </Link>
+          ))}
+        </div>
+      )}
+    </div>
+  )
+}