[cs] feat: 로그인 시 X-Device-Id 헤더 추가

apps/cs/src/entities/auth/api/auth-service.ts

@@ -10,6 +10,7 @@ import {
   getRemainingMs,
 } from "@common/auth";
 
+import { clearDeviceId, getOrCreateDeviceId } from "../lib/device-id";
 import {
   clearRefreshTimer,
   removeToken,
@@ -36,7 +37,10 @@ function resolveLoginError(message: string | undefined): string {
 async function login(payload: AuthPayload): Promise<void> {
   const response = await fetch(`/api/proxy${ENDPOINT.USER_SERVICE.LOGIN}`, {
     method: "POST",
-    headers: { "Content-Type": "application/json" },
+    headers: {
+      "Content-Type": "application/json",
+      "X-Device-Id": getOrCreateDeviceId(),
+    },
     body: JSON.stringify(payload),
   });
 
@@ -67,7 +71,12 @@ async function silentRefresh(): Promise<void> {
   try {
     const response = await fetch(
       `/api/proxy${ENDPOINT.USER_SERVICE.SILENT_REFRESH}`,
-      { method: "PUT" },
+      {
+        method: "PUT",
+        headers: {
+          "X-Device-Id": getOrCreateDeviceId(),
+        },
+      },
     );
 
     const data = await response.json();
@@ -105,6 +114,7 @@ async function silentRefresh(): Promise<void> {
 
 async function logout(): Promise<void> {
   tokenManager.clearAuthToken();
+  clearDeviceId();
   removeToken("site-id-key");
   removeToken("site-theme-key");
 

apps/cs/src/entities/auth/lib/device-id.ts

@@ -0,0 +1,20 @@
+import { v4 as uuidv4 } from "uuid";
+
+const DEVICE_ID_KEY = "x-device-id";
+
+export function getOrCreateDeviceId(): string {
+  if (typeof window === "undefined") return "";
+
+  const existing = localStorage.getItem(DEVICE_ID_KEY);
+  if (existing) return existing;
+
+  const id = uuidv4();
+  localStorage.setItem(DEVICE_ID_KEY, id);
+  return id;
+}
+
+export function clearDeviceId(): void {
+  if (typeof window === "undefined") return;
+
+  localStorage.removeItem(DEVICE_ID_KEY);
+}