Initial commit: thbd-portal, duplicated from elmi-portal

Rebranded for Thunderbird Portal (THBD): numbering prefix EL->TH, all
"ELMI"/"ЭЛМИ" UI strings genericized, ELMI's real contract templates and
company legal/bank details removed (not applicable to this company), fresh
VAPID keypair and encryption key, fresh single-migration schema history.
Same architecture as elmi-portal: Web Push notifications, unread-chat app
badge, cookie-session auth.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Gh2UXUQUVBWroWEnn1FLFG

src/app/(admin)/layout.tsx

@@ -0,0 +1,60 @@
+import { redirect } from "next/navigation";
+import Link from "next/link";
+import { Truck } from "lucide-react";
+import { getCurrentSession } from "@/lib/auth/session";
+import { LogoutButton } from "./logout-button";
+import { NavShell } from "./nav-shell";
+import { ThemeToggle } from "./theme-toggle";
+import { NotificationToggle } from "./notification-toggle";
+import { EventToasts } from "./event-toasts";
+import { PresenceHeartbeat } from "./presence-heartbeat";
+import { Avatar } from "./avatar";
+
+export default async function AdminLayout({ children }: { children: React.ReactNode }) {
+  const session = await getCurrentSession();
+  if (!session) {
+    redirect("/login");
+  }
+
+  const role = session.user.role as "admin" | "manager" | "accountant";
+
+  return (
+    // Fixed to the real visible viewport height (ViewportHeightFix keeps
+    // --app-vh in sync with window.visualViewport, which — unlike 100vh —
+    // actually shrinks under the on-screen keyboard) so header/nav stay
+    // pinned and only <main> scrolls, the standard "app shell" layout
+    // instead of the whole page scrolling under a header that reflows.
+    <div className="flex flex-col overflow-hidden bg-bg" style={{ height: "var(--app-vh)" }}>
+      <header className="shrink-0 border-b border-border bg-surface pt-[env(safe-area-inset-top)]">
+        <div className="mx-auto flex max-w-[1800px] items-center gap-3 px-4 py-2.5 sm:gap-6 sm:px-6 sm:py-3">
+          <Link href="/inquiries" className="flex shrink-0 items-center gap-2 font-display text-[15px] font-bold tracking-tight">
+            <div className="flex h-7 w-7 shrink-0 items-center justify-center rounded-md bg-accent text-white">
+              <Truck size={15} strokeWidth={2.5} />
+            </div>
+            <span className="hidden sm:inline">Thunderbird Portal</span>
+          </Link>
+          <div className="flex flex-1 justify-center overflow-x-auto">
+            <NavShell role={role} />
+          </div>
+          <div className="ml-auto flex shrink-0 items-center gap-2 sm:ml-0 sm:gap-3">
+            <NotificationToggle />
+            <ThemeToggle />
+            <Link href="/profile" className="flex items-center gap-2 rounded-md px-1.5 py-1 hover:bg-surface-hover">
+              <Avatar userId={session.user.id} name={session.user.name} hasAvatar={Boolean(session.user.avatarPath)} size={26} />
+              <span className="hidden text-sm text-text-muted sm:inline">{session.user.name}</span>
+            </Link>
+            <LogoutButton />
+          </div>
+        </div>
+      </header>
+
+      {/* pb: clears the fixed mobile bottom-tab bar (~52px + safe-area) so it never covers the last bit of scrolled content */}
+      <main className="app-shell-main mx-auto w-full max-w-[1800px] flex-1 overflow-y-auto px-4 py-6 pb-[calc(4.25rem+env(safe-area-inset-bottom))] sm:px-6 lg:pb-6">
+        {children}
+      </main>
+
+      <EventToasts currentUserId={session.user.id} />
+      <PresenceHeartbeat />
+    </div>
+  );
+}