✨(contacts) add "abilities" to API endpoint data

Returns the possible actions to the frontend using the
model's `get_abilities`.

src/backend/core/api/client/serializers.py

@@ -10,10 +10,13 @@ from core.models import ServiceProvider
 class ContactSerializer(serializers.ModelSerializer):
     """Serialize contacts."""
 
+    abilities = serializers.SerializerMethodField()
+
     class Meta:
         model = models.Contact
         fields = [
             "id",
+            "abilities",
             "override",
             "data",
             "full_name",
@@ -21,7 +24,7 @@ class ContactSerializer(serializers.ModelSerializer):
             "owner",
             "short_name",
         ]
-        read_only_fields = ["id", "owner"]
+        read_only_fields = ["id", "owner", "abilities"]
         extra_kwargs = {
             "override": {"required": False},
         }
@@ -31,6 +34,13 @@ class ContactSerializer(serializers.ModelSerializer):
         validated_data.pop("override", None)
         return super().update(instance, validated_data)
 
+    def get_abilities(self, contact) -> dict:
+        """Return abilities of the logged-in user on the instance."""
+        request = self.context.get("request")
+        if request:
+            return contact.get_abilities(request.user)
+        return {}
+
 
 class DynamicFieldsModelSerializer(serializers.ModelSerializer):
     """

src/backend/core/api/client/viewsets.py

@@ -137,7 +137,7 @@ class ContactViewSet(
     """Contact ViewSet"""
 
     permission_classes = [permissions.AccessPermission]
-    queryset = models.Contact.objects.all()
+    queryset = models.Contact.objects.select_related("user").all()
     serializer_class = serializers.ContactSerializer
     throttle_classes = [BurstRateThrottle, SustainedRateThrottle]
     ordering_fields = ["full_name", "short_name", "created_at"]