feat: 添加日记系统

- 完整的 Django 后端 (diary app)
- 前端页面
- 部署脚本 (本地 + 云端)
- Nginx 配置
- 数据迁移工具
- 同步工具

diary-system/backend/diary/serializers.py

@@ -0,0 +1,19 @@
+from rest_framework import serializers
+from .models import DiaryEntry, DailyProgress, Experience
+
+class ExperienceSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = Experience
+        fields = '__all__'
+
+class DailyProgressSerializer(serializers.ModelSerializer):
+    class Meta:
+        model = DailyProgress
+        fields = '__all__'
+
+class DiaryEntrySerializer(serializers.ModelSerializer):
+    progresses = DailyProgressSerializer(many=True, read_only=True)
+
+    class Meta:
+        model = DiaryEntry
+        fields = '__all__'