feat: 移除轮播图管理，系列活动改卡片布局，课程描述限10行，首页配置优化

backend/competition/serializers.py

@@ -1,6 +1,6 @@
 from rest_framework import serializers
 from django.conf import settings
-from .models import Competition, CompetitionEnrollment, ScoreDimension, Project, ProjectFile, Score, Comment, HomePageConfig, CarouselItem
+from .models import Competition, CompetitionEnrollment, ScoreDimension, Project, ProjectFile, Score, Comment, HomePageConfig
 from shop.serializers import WeChatUserSerializer
 
 
@@ -11,41 +11,16 @@ def _media_url(file_field):
     return None
 
 
-class CarouselItemSerializer(serializers.ModelSerializer):
-    display_image = serializers.SerializerMethodField()
-    
-    class Meta:
-        model = CarouselItem
-        fields = ['id', 'carousel_type', 'image', 'image_url', 'display_image', 
-                  'title', 'subtitle', 'status', 'status_color', 'date', 'location', 
-                  'order', 'is_active']
-    
-    def get_display_image(self, obj):
-        return _media_url(obj.image) or obj.image_url
-
-
 class HomePageConfigSerializer(serializers.ModelSerializer):
     display_banner = serializers.SerializerMethodField()
-    carousel1_items = serializers.SerializerMethodField()
-    carousel2_items = serializers.SerializerMethodField()
 
     class Meta:
         model = HomePageConfig
         fields = ['id', 'banner_image', 'banner_image_url', 'display_banner',
-                  'main_title', 'carousel1_title', 'carousel2_title',
-                  'organizer', 'undertaker', 'carousel1_items', 'carousel2_items']
-
+                  'main_title', 'organizer', 'undertaker']
     def get_display_banner(self, obj):
         return _media_url(obj.banner_image) or obj.banner_image_url
 
-    def get_carousel1_items(self, obj):
-        items = CarouselItem.objects.filter(carousel_type='carousel1', is_active=True)
-        return CarouselItemSerializer(items, many=True, context=self.context).data
-
-    def get_carousel2_items(self, obj):
-        items = CarouselItem.objects.filter(carousel_type='carousel2', is_active=True)
-        return CarouselItemSerializer(items, many=True, context=self.context).data
-
 
 class ScoreDimensionSerializer(serializers.ModelSerializer):
     class Meta: