Keep the TriggerShell wordmark visible on mobile

Only the icon-only nav links, username, and logout label needed to
collapse to fit a phone-width header - the brand text alone doesn't
push it over, so keep it always shown for identity.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

app/src/components/layout/nav.tsx

@@ -36,7 +36,7 @@ export function Nav({
             className="flex shrink-0 items-center gap-2 font-semibold tracking-tight"
           >
             <Terminal className="size-5" />
-            <span className="hidden sm:inline">TriggerShell</span>
+            TriggerShell
           </Link>
           <nav className="flex items-center gap-1">
             {links.map(({ href, label, icon: Icon }) => (