World Travel Improvements (#925)

* Security Patch Django 5.2.8

* Fix Menus on Safari Browser

* Enhance touch support and event handling for emoji picker and dropdown

* Add touch and pointer event handling to category selection for better mobile support

* Add PWA support for iOS/Safari with touch icons

* Refactor event listener for dropdown to use non-capturing 'click' for improved compatibility on Safari

* Enhance country and region description fetching from Wikipedia

- Refactor `generate_description_view.py` to improve candidate page selection and description retrieval.
- Update `CategoryDropdown.svelte` to simplify emoji selection handling and improve dropdown behavior.
- Add new translation keys in `en.json` for UI elements related to country descriptions.
- Modify `+page.svelte` and `+page.server.ts` in world travel routes to fetch and display country and region descriptions.
- Implement a toggle for showing full descriptions in the UI.

* Update Unraid installation documentation with improved variable formatting and additional resources

* Implement cache invalidation for visited regions and cities to ensure updated visit lists

* Add ClusterMap component for enhanced geographical data visualization

backend/server/worldtravel/views.py

@@ -14,6 +14,26 @@ from adventures.models import Location
 # Cache TTL
 CACHE_TTL = 60 * 60 * 24  # 1 day
 
+
+def invalidate_visit_caches_for_region_and_user(region, user):
+    """Invalidate cached visit lists for a given region and user.
+
+    Removes both the per-region and per-country per-user cache keys so
+    UI calls will refetch updated visited lists.
+    """
+    try:
+        if region is None or user is None:
+            return
+        # per-region cache
+        cache.delete(f"visits_by_region_{region.id}_{user.id}")
+        # per-country cache (region -> country -> country_code)
+        country_code = getattr(region.country, 'country_code', None)
+        if country_code:
+            cache.delete(f"visits_by_country_{country_code}_{user.id}")
+    except Exception:
+        # Avoid raising cache-related exceptions; best-effort invalidation
+        pass
+
 @cache_page(CACHE_TTL)
 @api_view(['GET'])
 @permission_classes([IsAuthenticated])
@@ -138,13 +158,22 @@ class VisitedRegionViewSet(viewsets.ModelViewSet):
         serializer.is_valid(raise_exception=True)
         self.perform_create(serializer)
         headers = self.get_success_headers(serializer.data)
+        # Invalidate caches for this region and its country for the user
+        try:
+            region = serializer.validated_data.get('region')
+            invalidate_visit_caches_for_region_and_user(region, request.user)
+        except Exception:
+            pass
         return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers)
     
     def destroy(self, request, **kwargs):
         region = get_object_or_404(Region, id=kwargs['pk'])
         visited_region = VisitedRegion.objects.filter(user=request.user.id, region=region)
         if visited_region.exists():
+            # capture region before deleting so we can invalidate caches
+            affected_region = visited_region.first().region
             visited_region.delete()
+            invalidate_visit_caches_for_region_and_user(affected_region, request.user)
             return Response(status=status.HTTP_204_NO_CONTENT)
         else:
             return Response({"error": "Visited region not found."}, status=status.HTTP_404_NOT_FOUND)
@@ -164,9 +193,14 @@ class VisitedCityViewSet(viewsets.ModelViewSet):
         serializer = self.get_serializer(data=request.data)
         serializer.is_valid(raise_exception=True)
         self.perform_create(serializer)
+        # Ensure a VisitedRegion exists for the city and invalidate caches
         region = serializer.validated_data['city'].region
         if not VisitedRegion.objects.filter(user=request.user.id, region=region).exists():
             VisitedRegion.objects.create(user=request.user, region=region)
+        try:
+            invalidate_visit_caches_for_region_and_user(region, request.user)
+        except Exception:
+            pass
         headers = self.get_success_headers(serializer.data)
         return Response(serializer.data, status=status.HTTP_201_CREATED, headers=headers)
     
@@ -174,7 +208,9 @@ class VisitedCityViewSet(viewsets.ModelViewSet):
         city = get_object_or_404(City, id=kwargs['pk'])
         visited_city = VisitedCity.objects.filter(user=request.user.id, city=city)
         if visited_city.exists():
+            region = city.region
             visited_city.delete()
+            invalidate_visit_caches_for_region_and_user(region, request.user)
             return Response(status=status.HTTP_204_NO_CONTENT)
         else:
             return Response({"error": "Visited city not found."}, status=status.HTTP_404_NOT_FOUND)