Don't render full category information in part API

- Lots of data duplication!
- Just send the category ID (and the category name)
-

InvenTree/part/serializers.py

@@ -43,7 +43,7 @@ class PartSerializer(serializers.ModelSerializer):
     """
 
     url = serializers.CharField(source='get_absolute_url', read_only=True)
-    category = CategorySerializer(many=False, read_only=True)
+    category_name = serializers.CharField(source='category_path', read_only=True)
 
     class Meta:
         model = Part
@@ -55,6 +55,7 @@ class PartSerializer(serializers.ModelSerializer):
             'URL',  # Link to an external URL (optional)
             'description',
             'category',
+            'category_name',
             'total_stock',
             'available_stock',
             'units',