chore(import): improve error handling and add flyer integration

- Replace BadRequestException with UnauthorizedException for authentication failures in flyer-import and flyer-selection controllers
- Add bulk selection endpoint in FlyerSelectionController for creating multiple selections in one request
- Update FlyerSelectionModule to include new FlyerSelectionMatcherService and FlyerSelectionSyncController
- Extend FlyerSelectionService with createMany method for bulk operations
- Add new DTOs for bulk selection and receipt matching functionality
- Update ReceiptImportService to accept FlyerSelectionService dependency and track successful rows
- Extend SaveReceiptResponse with flyerAutoSync field for receipt-to-flyer matching results
- Add new API paths for flyer import and selection endpoints
- Update Flutter UI to include Flyer import tab and adjust tab controller length
- Add new domain models and repository methods for flyer import functionality
- Update test files to include new FlyerSelectionService dependency
- Modify .kilo plan documentation to reflect current system architecture

flutter/lib/core/ui/app_shell.dart

@@ -142,13 +142,17 @@ class AppShell extends ConsumerWidget {
                     icon: Icon(Icons.restaurant_menu_outlined),
                     text: 'Recept',
                   ),
-                  Tab(
-                    icon: Icon(Icons.receipt_long_outlined),
-                    text: 'Kvitto',
-                  ),
-                ],
-              )
-            : null,
+                  Tab(
+                    icon: Icon(Icons.receipt_long_outlined),
+                    text: 'Kvitto',
+                  ),
+                  Tab(
+                    icon: Icon(Icons.local_offer_outlined),
+                    text: 'Flyer',
+                  ),
+                ],
+              )
+            : null,
         actions: [
           if (isRecipesRoute)
             Consumer(
@@ -278,9 +282,9 @@ class AppShell extends ConsumerWidget {
             ),
     );
 
-    if (isImportRoute) {
-      shell = DefaultTabController(length: 2, child: shell);
-    }
+    if (isImportRoute) {
+      shell = DefaultTabController(length: 3, child: shell);
+    }
 
     return shell;
   }