feat(compliance): content moderation on model input and output — local lexicon, Aliyun adapter, free completion, admin log

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01N4f2nya58RoRu4yEmJgRGE

frontend/src/components/admin/admin-app.tsx

@@ -121,6 +121,7 @@ export function AdminApp({ children }: { children: ReactNode }) {
               { name: "feature-flags", list: "/admin/feature-flags", meta: { label: "功能开关", icon: <ControlOutlined /> } },
               { name: "security", list: "/admin/security", meta: { label: "安全验证", icon: <SafetyCertificateOutlined /> } },
               { name: "audit-logs", list: "/admin/audit-logs", meta: { label: "审计日志", icon: <AuditOutlined /> } },
+              { name: "moderation-events", list: "/admin/moderation-events", meta: { label: "内容审核", icon: <AuditOutlined /> } },
             ]}
             options={{
               syncWithLocation: true,