docs: 优化多个 README 文件中的命令格式

- 移除了不必要的 mkdir 命令中的 && 符号
- 更新了 curl 命令格式，从 -fsSL 改为 -fSL
- 添加了 Python 脚本说明文档
- 新增了删除空文件夹的 Python 脚本

nginx/37point2.cn/README.md

@@ -9,11 +9,11 @@ mkdir -p /var/www/37point2.cn
 下载配置
 
 ```bash
-curl -fsSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/37point2.cn/index.html > /var/www/37point2.cn/index.html
+curl -fSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/37point2.cn/index.html > /var/www/37point2.cn/index.html
 ```
 
 ```bash
-curl -fsSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/37point2.cn/nginx.conf > /etc/nginx/sites-available/37point2.cn
+curl -fSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/37point2.cn/nginx.conf > /etc/nginx/sites-available/37point2.cn
 ```
 
 启用配置

nginx/README.md

@@ -31,7 +31,7 @@ systemctl status nginx
 下载配置
 
 ```bash
-curl -fsSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/nginx.conf > /etc/nginx/nginx.conf
+curl -fSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/nginx.conf > /etc/nginx/nginx.conf
 ```
 
 测试配置

nginx/example/README.md

@@ -3,7 +3,7 @@
 下载配置
 
 ```bash
-curl -fsSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/example/nginx.conf > /etc/nginx/sites-available/example.com
+curl -fSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/example/nginx.conf > /etc/nginx/sites-available/example.com
 ```
 
 启用配置

nginx/note.sugarscat.cn/README.md

@@ -7,7 +7,7 @@ mkdir -p /opt/www/note && cd /opt/www/note
 ```
 
 ```bash
-curl -fsSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/note.sugarscat.cn/deploy.sh > deploy.sh && chmod +x deploy.sh
+curl -fSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/note.sugarscat.cn/deploy.sh > deploy.sh && chmod +x deploy.sh
 ```
 
 ## 定时执行脚本
@@ -35,7 +35,7 @@ crontab -l
 下载配置
 
 ```bash
-curl -fsSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/note.sugarscat.cn/nginx.conf > /etc/nginx/sites-available/note.sugarscat.cn
+curl -fSL https://i.sugarscat.cn/me/script/-/raw/main/nginx/note.sugarscat.cn/nginx.conf > /etc/nginx/sites-available/note.sugarscat.cn
 ```
 
 启用配置