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/router/component-loaders/extensions.js

@@ -1,5 +1,4 @@
 export const extensionsPageLoaders = {
   ExtensionTools: () => import('@/pages/extensions/ExtensionTools.vue'),
-  ExtensionSecurity: () => import('@/pages/extensions/ExtensionSecurity.vue'),
   ExtensionAI: () => import('@/pages/extensions/ExtensionAI.vue'),
 }