fix: add auth guard redirect and wire logout into NavAccountCard

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/components/layout/sidebar.tsx

@@ -8,13 +8,12 @@ import {
     faGrid2,
     faPlug,
 } from "@fortawesome/pro-regular-svg-icons";
+import { useNavigate } from "react-router";
 import { MobileNavigationHeader } from "@/components/application/app-navigation/base-components/mobile-header";
 import { NavAccountCard } from "@/components/application/app-navigation/base-components/nav-account-card";
 import { NavItemBase } from "@/components/application/app-navigation/base-components/nav-item";
 import type { NavItemType } from "@/components/application/app-navigation/config";
-
-// TODO: Wire to useAuth() once auth-provider.tsx is implemented
-const isAdmin = false;
+import { useAuth } from "@/providers/auth-provider";
 
 const MAIN_SIDEBAR_WIDTH = 292;
 
@@ -58,10 +57,18 @@ interface SidebarProps {
 }
 
 export const Sidebar = ({ activeUrl = "/" }: SidebarProps) => {
+    const { logout, isAdmin: authIsAdmin, user } = useAuth();
+    const navigate = useNavigate();
+
+    const handleSignOut = () => {
+        logout();
+        navigate('/login');
+    };
+
     const navSections = [
         { label: "Main", items: mainItems },
         { label: "Insights", items: insightsItems },
-        ...(isAdmin ? [{ label: "Admin", items: adminItems }] : []),
+        ...(authIsAdmin ? [{ label: "Admin", items: adminItems }] : []),
     ];
 
     const content = (
@@ -103,7 +110,7 @@ export const Sidebar = ({ activeUrl = "/" }: SidebarProps) => {
 
             {/* Account card */}
             <div className="mt-auto flex flex-col gap-5 px-2 py-4 lg:gap-6 lg:px-4 lg:py-4">
-                <NavAccountCard />
+                <NavAccountCard onSignOut={handleSignOut} />
             </div>
         </aside>
     );