feat(deploy): add Ubuntu 26.04 production package

infra/ubuntu/scripts/install-backup-timer.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+set -Eeuo pipefail
+
+if [[ "${EUID}" -ne 0 ]]; then
+  echo '请使用 sudo 运行此脚本。' >&2
+  exit 1
+fi
+
+script_dir="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
+ubuntu_dir="$(cd -- "$script_dir/.." && pwd)"
+repo_root="$(cd -- "$ubuntu_dir/../.." && pwd)"
+[[ "$repo_root" == '/opt/lehuo/app' ]] || {
+  echo '安装定时器前请把仓库部署到 /opt/lehuo/app。' >&2
+  exit 1
+}
+[[ -f /etc/lehuo/lehuo.env ]] || { echo '缺少 /etc/lehuo/lehuo.env。' >&2; exit 1; }
+
+install -m 0644 "$ubuntu_dir/systemd/lehuo-backup.service" /etc/systemd/system/lehuo-backup.service
+install -m 0644 "$ubuntu_dir/systemd/lehuo-backup.timer" /etc/systemd/system/lehuo-backup.timer
+systemctl daemon-reload
+systemctl enable --now lehuo-backup.timer
+systemctl list-timers lehuo-backup.timer --no-pager
+
+echo '每日备份定时器已安装。首次正式发布前仍须手工执行一次备份和恢复演练。'