toggle feedack better handle

lib/view_models/tenders_view_model.dart

@@ -253,16 +253,62 @@ class TendersViewModel with ChangeNotifier {
     required String feedbackType,
   }) async {
     _feedbackErrorMessage = null;
+
+    // Get current feedback for this tender
+    final existingFeedback = getFeedbackForTender(tenderId);
+    final existingFeedbackIndex = feedbacks.indexWhere(
+      (f) => f.tender == tenderId,
+    );
+
+    // Create optimistic feedback data
+    FeedbackData? optimisticFeedback;
+
+    if (existingFeedback == null) {
+      // No existing feedback - create new optimistic feedback
+      optimisticFeedback = FeedbackData(
+        companyId: null, // Will be filled by server
+        createdAt: DateTime.now().millisecondsSinceEpoch,
+        customerId: null, // Will be filled by server
+        feedbackType: feedbackType,
+        id: null, // Will be filled by server
+        tender: tenderId,
+        updatedAt: DateTime.now().millisecondsSinceEpoch,
+      );
+      feedbacks.add(optimisticFeedback);
+    } else {
+      // Existing feedback - update optimistically
+      if (existingFeedback.feedbackType == feedbackType) {
+        // Same feedback type - remove feedback (toggle off)
+        if (existingFeedbackIndex != -1) {
+          feedbacks.removeAt(existingFeedbackIndex);
+        }
+        optimisticFeedback = null;
+      } else {
+        // Different feedback type - update to new type
+        optimisticFeedback = existingFeedback.copyWith(
+          feedbackType: feedbackType,
+          updatedAt: DateTime.now().millisecondsSinceEpoch,
+        );
+        if (existingFeedbackIndex != -1) {
+          feedbacks[existingFeedbackIndex] = optimisticFeedback;
+        }
+      }
+    }
+
+    // Notify listeners immediately for optimistic update
     notifyListeners();
 
+    // Call API
     final result = await _tendersRepository.toggleFeedback(
       tenderId: tenderId,
       feedbackType: feedbackType,
     );
+
     switch (result) {
       case Ok<FeedbackResponse>():
         _feedbackData = result.value.data;
         if (_feedbackData != null) {
+          // Update with complete data from server
           final index = feedbacks.indexWhere(
             (f) => f.tender == _feedbackData!.tender,
           );
@@ -271,12 +317,31 @@ class TendersViewModel with ChangeNotifier {
           } else {
             feedbacks.add(_feedbackData!);
           }
+        } else {
+          // Server returned null data - remove feedback
+          feedbacks.removeWhere((f) => f.tender == tenderId);
         }
         break;
       case Error<FeedbackResponse>():
+        // Revert optimistic update on error
+        if (existingFeedback == null) {
+          // Remove the optimistic feedback we added
+          feedbacks.removeWhere((f) => f.tender == tenderId);
+        } else {
+          // Restore the original feedback - find current index and update, or add if not found
+          final currentIndex = feedbacks.indexWhere(
+            (f) => f.tender == tenderId,
+          );
+          if (currentIndex != -1) {
+            feedbacks[currentIndex] = existingFeedback;
+          } else {
+            feedbacks.add(existingFeedback);
+          }
+        }
         _feedbackErrorMessage = result.error.toString();
         break;
     }
+
     notifyListeners();
     _feedbackErrorMessage = null;
     notifyListeners();