fix sync

lib/services/pb_sync_service.dart

@@ -335,6 +335,22 @@ class PbSyncService {
     );
   }
 
+  /// Cheap remote count for stale detection (1 row, with totals).
+  Future<int> countTransactions() async {
+    final userId = _userId;
+    final filter = 'user="$userId"';
+    final result = await _withTimeout(
+      _pb.collection('transactions').getList(
+            page: 1,
+            perPage: 1,
+            filter: filter,
+            skipTotal: false,
+          ),
+      label: 'transactions count',
+    );
+    return result.totalItems;
+  }
+
   /// Pulls the full bank transaction list for the signed-in user.
   Future<List<BankTransaction>> pullTransactions({
     void Function(double progress)? onProgress,