Fix login loop on self-hosted desktop (#5022)

# Description of Changes
Fix #5017 

Changes the handling of jwt tokens to be stored in local storage as well
as OS keyring so the rest of the app knows that you're logged in.

frontend/src/proprietary/auth/UseSession.tsx

@@ -126,6 +126,14 @@ export function AuthProvider({ children }: { children: ReactNode }) {
 
     initializeAuth();
 
+    // Listen for jwt-available event (triggered by desktop auth or other sources)
+    const handleJwtAvailable = () => {
+      console.debug('[Auth] JWT available event received, refreshing session');
+      void initializeAuth();
+    };
+
+    window.addEventListener('jwt-available', handleJwtAvailable);
+
     // Subscribe to auth state changes
     const { data: { subscription } } = springAuth.onAuthStateChange(
       async (event: AuthChangeEvent, newSession: Session | null) => {
@@ -162,6 +170,7 @@ export function AuthProvider({ children }: { children: ReactNode }) {
 
     return () => {
       mounted = false;
+      window.removeEventListener('jwt-available', handleJwtAvailable);
       subscription.unsubscribe();
     };
   }, []);

frontend/src/proprietary/auth/springAuthClient.ts

@@ -161,8 +161,8 @@ class SpringAuthClient {
         return { data: { session: null }, error: null };
       }
 
-      // Clear potentially invalid token on other errors too
-      localStorage.removeItem('stirling_jwt');
+      // Don't clear token for other errors (e.g., backend not ready, network issues)
+      // The token is still valid, just can't verify it right now
       return {
         data: { session: null },
         error: { message: getErrorMessage(error, 'Unknown error') },

frontend/src/proprietary/routes/Login.tsx

@@ -8,6 +8,8 @@ import { useTranslation } from 'react-i18next';
 import { useDocumentMeta } from '@app/hooks/useDocumentMeta';
 import AuthLayout from '@app/routes/authShared/AuthLayout';
 import { useBackendProbe } from '@app/hooks/useBackendProbe';
+import apiClient from '@app/services/apiClient';
+import { BASE_PATH } from '@app/constants/app';
 
 // Import login components
 import LoginHeader from '@app/routes/login/LoginHeader';
@@ -16,7 +18,6 @@ import EmailPasswordForm from '@app/routes/login/EmailPasswordForm';
 import OAuthButtons, { DEBUG_SHOW_ALL_PROVIDERS, oauthProviderConfig } from '@app/routes/login/OAuthButtons';
 import DividerWithText from '@app/components/shared/DividerWithText';
 import LoggedInState from '@app/routes/login/LoggedInState';
-import { BASE_PATH } from '@app/constants/app';
 
 export default function Login() {
   const navigate = useNavigate();
@@ -85,30 +86,28 @@ export default function Login() {
   useEffect(() => {
     const fetchProviders = async () => {
       try {
-        const response = await fetch(`${BASE_PATH}/api/v1/proprietary/ui-data/login`);
-        if (response.ok) {
-          const data = await response.json();
+        const response = await apiClient.get('/api/v1/proprietary/ui-data/login');
+        const data = response.data;
 
-          // Check if login is disabled - if so, redirect to home
-          if (data.enableLogin === false) {
-            console.debug('[Login] Login disabled, redirecting to home');
-            navigate('/');
-            return;
-          }
-
-          setEnableLogin(data.enableLogin ?? true);
-
-          // Set first-time setup flags
-          setIsFirstTimeSetup(data.firstTimeSetup ?? false);
-          setShowDefaultCredentials(data.showDefaultCredentials ?? false);
-
-          // Extract provider IDs from the providerList map
-          // The keys are like "/oauth2/authorization/google" - extract the last part
-          const providerIds = Object.keys(data.providerList || {})
-            .map(key => key.split('/').pop())
-            .filter((id): id is string => id !== undefined);
-          setEnabledProviders(providerIds);
+        // Check if login is disabled - if so, redirect to home
+        if (data.enableLogin === false) {
+          console.debug('[Login] Login disabled, redirecting to home');
+          navigate('/');
+          return;
         }
+
+        setEnableLogin(data.enableLogin ?? true);
+
+        // Set first-time setup flags
+        setIsFirstTimeSetup(data.firstTimeSetup ?? false);
+        setShowDefaultCredentials(data.showDefaultCredentials ?? false);
+
+        // Extract provider IDs from the providerList map
+        // The keys are like "/oauth2/authorization/google" - extract the last part
+        const providerIds = Object.keys(data.providerList || {})
+          .map(key => key.split('/').pop())
+          .filter((id): id is string => id !== undefined);
+        setEnabledProviders(providerIds);
       } catch (err) {
         console.error('[Login] Failed to fetch enabled providers:', err);
       }