Design, implement, and operate encrypted restic backups for Linux home directories with systemd automation, retention policies, and restore validation. Use when a user asks to back up ~/, set up daily/weekly/monthly backup jobs, harden backup security, or troubleshoot restore/integrity issues.

为 Linux 家目录设计、实施和运行加密的 restic 备份，结合 systemd 自动化、保留策略和恢复验证。当用户请求备份 ~/、设置每日/每周/每月备份任务、加强备份安全或排查恢复/完整性问题时使用。