⚡️(frontend) prevent authentication retry on 401 responses

Stop retry attempts when receiving 401 Unauthorized from /me endpoint since
this clearly indicates authentication status. The original purpose of the /me
call is simply to determine if user is authenticated, and a 401 provides
sufficient information.

Prevents unnecessary network requests caused by React Query's automatic retry
behavior when re-raising exceptions, which was hiding the 401 status. Improves
performance and reduces server load during authentication failures.

src/frontend/apps/impress/src/core/AppProvider.tsx

@@ -9,6 +9,8 @@ import { useResponsiveStore } from '@/stores/';
 
 import { ConfigProvider } from './config/';
 
+export const DEFAULT_QUERY_RETRY = 1;
+
 /**
  * QueryClient:
  *  - defaultOptions:
@@ -19,7 +21,7 @@ import { ConfigProvider } from './config/';
 const defaultOptions = {
   queries: {
     staleTime: 1000 * 60 * 3,
-    retry: 1,
+    retry: DEFAULT_QUERY_RETRY,
   },
 };
 const queryClient = new QueryClient({

src/frontend/apps/impress/src/features/auth/api/useAuthQuery.tsx

@@ -1,9 +1,12 @@
 import { UseQueryOptions, useQuery } from '@tanstack/react-query';
 
 import { APIError, errorCauses, fetchAPI } from '@/api';
+import { DEFAULT_QUERY_RETRY } from '@/core';
 
 import { User } from './types';
 
+type UserResponse = User | null;
+
 /**
  * Asynchronously retrieves the current user's data from the API.
  * This function is called during frontend initialization to check
@@ -14,8 +17,13 @@ import { User } from './types';
  * @throws {Error} Throws an error if the API request fails.
  * @returns {Promise<User>} A promise that resolves to the user data.
  */
-export const getMe = async (): Promise<User> => {
+export const getMe = async (): Promise<UserResponse> => {
   const response = await fetchAPI(`users/me/`);
+
+  if (response.status === 401) {
+    return null;
+  }
+
   if (!response.ok) {
     throw new APIError(
       `Couldn't fetch user data: ${response.statusText}`,
@@ -28,12 +36,19 @@ export const getMe = async (): Promise<User> => {
 export const KEY_AUTH = 'auth';
 
 export function useAuthQuery(
-  queryConfig?: UseQueryOptions<User, APIError, User>,
+  queryConfig?: UseQueryOptions<UserResponse, APIError, UserResponse>,
 ) {
-  return useQuery<User, APIError, User>({
+  return useQuery<UserResponse, APIError, UserResponse>({
     queryKey: [KEY_AUTH],
     queryFn: getMe,
     staleTime: 1000 * 60 * 15, // 15 minutes
+    retry: (failureCount, error) => {
+      // we assume that a 401 means the user is not logged in
+      if (error.status == 401) {
+        return false;
+      }
+      return failureCount < DEFAULT_QUERY_RETRY;
+    },
     ...queryConfig,
   });
 }

src/frontend/apps/impress/src/features/language/hooks/useSynchronizedLanguage.ts

@@ -22,7 +22,7 @@ export const useSynchronizedLanguage = () => {
   );
 
   const changeBackendLanguage = useCallback(
-    async (language: string, user?: User) => {
+    async (language: string, user?: User | null) => {
       const closestBackendLanguage = getMatchingLocales(
         availableBackendLanguages,
         [language],
@@ -52,7 +52,7 @@ export const useSynchronizedLanguage = () => {
   );
 
   const changeLanguageSynchronized = useCallback(
-    async (language: string, user?: User) => {
+    async (language: string, user?: User | null) => {
       if (!isSynchronizingLanguage.current) {
         isSynchronizingLanguage.current = true;
         await changeFrontendLanguage(language);