feat(auth): add backend logout API and integrate logout flow

src/app/api/auth/logout/route.ts

@@ -0,0 +1,60 @@
+import { NextRequest, NextResponse } from "next/server";
+import { getRequestToken } from "@/app/api/_auth";
+
+interface UpstreamAuthResponse {
+  data?: unknown;
+  message?: unknown;
+  status?: unknown;
+}
+
+const UPSTREAM_LOGOUT_PATH = "/api_client/auth/logout";
+
+function getUpstreamUrl(request: NextRequest): string {
+  const baseUrl =
+    process.env.POPIART_API_BASE_URL ||
+    process.env.NEXT_PUBLIC_APP_URL ||
+    request.nextUrl.origin;
+  return baseUrl.replace(/\/+$/, "") + UPSTREAM_LOGOUT_PATH;
+}
+
+async function logout(request: NextRequest, method: "GET" | "POST") {
+  try {
+    const token = getRequestToken(request);
+    const headers: Record<string, string> = {
+      Accept: "application/json",
+    };
+
+    if (token) {
+      headers.Authorization = `Bearer ${token}`;
+      headers.token = token;
+    }
+
+    const response = await fetch(getUpstreamUrl(request), {
+      method,
+      headers,
+      cache: "no-store",
+    });
+
+    const responseBody = (await response.json()) as UpstreamAuthResponse;
+    return NextResponse.json<UpstreamAuthResponse>(responseBody, {
+      status: response.status,
+    });
+  } catch (error) {
+    console.error("Error logging out:", error);
+    return NextResponse.json<UpstreamAuthResponse>(
+      {
+        status: "0500",
+        message: "Failed to logout",
+      },
+      { status: 500 }
+    );
+  }
+}
+
+export async function POST(request: NextRequest) {
+  return logout(request, "POST");
+}
+
+export async function GET(request: NextRequest) {
+  return logout(request, "GET");
+}

src/components/auth/HeaderUserMenu.tsx

@@ -10,11 +10,31 @@ import { useUserStore } from "@/store/userStore";
 export function HeaderUserMenu() {
   const { t } = useI18n();
   const [showUserMenu, setShowUserMenu] = useState(false);
-  const { userInfo, clearSession } = useUserStore(useShallow((state) => ({
+  const { token, userInfo, clearSession } = useUserStore(useShallow((state) => ({
+    token: state.token,
     userInfo: state.userInfo,
     clearSession: state.clearSession,
   })));
 
+  const handleLogout = async () => {
+    try {
+      const headers = new Headers({ Accept: "application/json" });
+      if (token?.trim()) {
+        headers.set("Authorization", `Bearer ${token.trim()}`);
+        headers.set("token", token.trim());
+      }
+
+      await fetch("/api/auth/logout", {
+        method: "POST",
+        headers,
+        cache: "no-store",
+      });
+    } finally {
+      clearSession();
+      setShowUserMenu(false);
+    }
+  };
+
   if (!userInfo) {
     return (
       <button
@@ -57,10 +77,7 @@ export function HeaderUserMenu() {
       <button
         type="button"
         className="mt-3 w-full rounded-lg border border-neutral-800 px-3 py-2 text-left text-sm text-neutral-300 transition-colors hover:border-neutral-700 hover:bg-neutral-900 hover:text-neutral-100"
-        onClick={() => {
-          clearSession();
-          setShowUserMenu(false);
-        }}
+        onClick={() => void handleLogout()}
       >
         {t("auth.logout")}
       </button>