feat(deploy): 添加开发环境 systemd 服务，改进部署文档

rust-backend-dev.service

@@ -0,0 +1,28 @@
+[Unit]
+Description=Rust Backend Development Service
+After=network.target postgresql.service
+Wants=network.target
+
+[Service]
+Type=simple
+User=root
+Group=root
+WorkingDirectory=/root/rust/rust_backend_dev
+ExecStart=/root/rust/rust_backend_dev/rust-backend
+Restart=always
+RestartSec=5
+StandardOutput=journal
+StandardError=journal
+
+EnvironmentFile=/root/rust/rust_backend_dev/.env
+
+NoNewPrivileges=yes
+PrivateTmp=yes
+ProtectSystem=strict
+ProtectHome=read-only
+ReadWritePaths=/root/rust/rust_backend_dev
+
+SyslogIdentifier=rust-backend-dev
+
+[Install]
+WantedBy=multi-user.target