refactor(admin): consolidate duplicate configuration

Remove duplicate comment, captcha, filing, and website-security configuration paths.

Move front submission verification to the captcha scene matrix and retire obsolete admin routes and components.

assets/admin/src/constants/sections/extensions.js

@@ -36,15 +36,6 @@ export const extensionsSection = {
       canonicalDomain: 'extensions',
       section: 'push',
     }),
-    customPage({
-      key: 'extensions-security',
-      name: 'ExtensionsSecurity',
-      label: '网站安全',
-      route: '/extensions/security',
-      component: 'ExtensionSecurity',
-      title: '网站安全',
-      desc: '扩展安全策略和第三方安全集成。',
-    }),
     customPage({
       key: 'extensions-tools',
       name: 'ExtensionsTools',