Make the app an installable PWA with phone layout and Web Push

Add a generated manifest, icon set, offline page and service worker that never caches authenticated HTML, plus install and update UI. Turn the rail into a drawer below md with container-query internals, dvh and safe-area handling, and reconnect the socket after visibility/network changes. Add Web Push subscriptions, presence-aware delivery, notification settings and tests.

src/layouts/bots/(partials)/rail-section-label.tsx

@@ -18,13 +18,13 @@ type Props = {
 export default function RailSectionLabel({ title, action }: Props) {
     return (
         <>
-            <Row className="hidden lg:flex shrink-0 h-8 mt-3 gap-2! flex-nowrap items-center justify-between px-3">
+            <Row className="hidden @rail:flex shrink-0 h-8 mt-3 gap-2! flex-nowrap items-center justify-between px-3">
                 <Span className="text-[11px] font-bold uppercase tracking-wide leading-4 text-ink-secondary">
                     {title}
                 </Span>
                 {action}
             </Row>
-            <Divider className="lg:hidden shrink-0 mx-1 my-2 w-auto border-hairline dark:border-hairline" />
+            <Divider className="@rail:hidden shrink-0 mx-1 my-2 w-auto border-hairline dark:border-hairline" />
         </>
     );
 }