feat(pages): configurable limits, multi-format packages, and dual versioning

Make Pages package size and history retention system-configurable, support
zip/tar.gz/tar.xz/tar.bz2/tar/7z uploads, prune history with clear keep-N
semantics, and rebind agent config to the live active Pages deployment so
main-config rollback never depends on pruned packages.

frontend/app/(main)/pages/page.tsx

@@ -30,7 +30,8 @@ export default function PagesPage() {
           <div>
             <h1 className='text-2xl font-semibold tracking-tight'>Pages</h1>
             <p className='text-sm text-muted-foreground'>
-              边缘静态站点托管，上传 zip 部署包并在代理规则中选择 Pages 上游。
+              边缘静态站点托管，上传静态资源部署包并在代理规则中选择 Pages
+              上游。
             </p>
           </div>
         </div>