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/nginx_cloud.conf

@@ -0,0 +1,23 @@
+server {
+    listen 8001;
+    server_name _;
+
+    location = /favicon.ico { access_log off; log_not_found off; }
+    
+    location /static/ {
+        alias /home/ubuntu/diary-system/backend/static/;
+    }
+
+    location /api/ {
+        proxy_pass http://127.0.0.1:8002;
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    }
+
+    location / {
+        root /home/ubuntu/diary-system/frontend;
+        index index.html;
+        try_files $uri $uri/ /index.html;
+    }
+}