fix: Keep every scan in history (no dedup by URL)

Each scan is a separate entry so users can track changes over time.
Increased max entries from 20 to 50.

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

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

@@ -98,7 +98,7 @@ export default function AgentPage() {
       findings: result.findings?.length || 0,
       docs: result.discovered_documents?.length || 0,
     }
-    const updated = [entry, ...scanHistory.filter(h => h.url !== entry.url)].slice(0, 20)
+    const updated = [entry, ...scanHistory].slice(0, 50)
     setScanHistory(updated)
     localStorage.setItem('agent-scan-history', JSON.stringify(updated))
   }