auth: use sessions

lib/features/home/home_page.dart

@@ -103,9 +103,11 @@ class _HomePageState extends State<HomePage> with RouteAware {
 
   Future<SyncResult> _loadSheets() async {
     final url = await _storageService.readSecure(SecureStorageKey.url);
-    final jwt = await _storageService.readSecure(SecureStorageKey.jwt);
+    final refreshToken = await _storageService.readSecure(
+      SecureStorageKey.refreshToken,
+    );
 
-    _apiClient = ApiClient(baseUrl: url!, token: jwt);
+    _apiClient = ApiClient(baseUrl: url!, refreshToken: refreshToken);
     _syncService = SyncService(
       apiClient: _apiClient!,
       storageService: _storageService,
@@ -169,6 +171,7 @@ class _HomePageState extends State<HomePage> with RouteAware {
 
   Future<void> _handleLogout() async {
     await _storageService.clearAllUserData();
+    await _apiClient!.logout();
 
     if (!mounted) return;