rpi: бэкап OneDrive на HDD + SMART/бэкап-метрики через pushgateway на fr1

- servers/rpi.md: новая домашняя Raspberry Pi 4 (Trixie, cloud-init), HDD 4 ТБ,
  грабли с питанием двух HDD от USB
- stacks/rpi-backup: rclone sync с вечным архивом версий, еженедельная сверка
  хэшей, smartd, пуш SMART и статуса бэкапов
- fr1: pushgateway (127.0.0.1:9091), приём по SSH через forced command
  ~/bin/pushgw-ingest, алерты группы rpi

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

stacks/rpi-backup/systemd/onedrive-backup.service

@@ -0,0 +1,14 @@
+[Unit]
+Description=OneDrive -> HDD backup (rclone)
+Wants=network-online.target
+After=network-online.target
+RequiresMountsFor=/mnt/backup
+
+[Service]
+Type=oneshot
+User=rus
+ExecStart=/usr/bin/flock /run/lock/onedrive-backup.lock /usr/local/bin/onedrive-backup
+ExecStopPost=+/usr/local/bin/backup-metrics backup_onedrive
+Nice=10
+IOSchedulingClass=idle
+TimeoutStartSec=infinity

stacks/rpi-backup/systemd/onedrive-backup.timer

@@ -0,0 +1,10 @@
+[Unit]
+Description=OneDrive backup every 4h
+
+[Timer]
+OnCalendar=*-*-* 00/4:30
+RandomizedDelaySec=5m
+Persistent=true
+
+[Install]
+WantedBy=timers.target

stacks/rpi-backup/systemd/onedrive-verify.service

@@ -0,0 +1,14 @@
+[Unit]
+Description=OneDrive backup integrity check
+Wants=network-online.target
+After=network-online.target onedrive-backup.service
+RequiresMountsFor=/mnt/backup
+
+[Service]
+Type=oneshot
+User=rus
+ExecStart=/usr/bin/flock /run/lock/onedrive-backup.lock /usr/local/bin/onedrive-verify
+ExecStopPost=+/usr/local/bin/backup-metrics backup_onedrive_verify
+Nice=15
+IOSchedulingClass=idle
+TimeoutStartSec=infinity

stacks/rpi-backup/systemd/onedrive-verify.timer

@@ -0,0 +1,9 @@
+[Unit]
+Description=Weekly OneDrive backup integrity check
+
+[Timer]
+OnCalendar=Sun *-*-* 05:00
+Persistent=true
+
+[Install]
+WantedBy=timers.target

stacks/rpi-backup/systemd/smart-metrics.service

@@ -0,0 +1,8 @@
+[Unit]
+Description=Push SMART metrics to pushgateway on fr1
+Wants=network-online.target
+After=network-online.target
+
+[Service]
+Type=oneshot
+ExecStart=/usr/local/bin/smart-metrics

stacks/rpi-backup/systemd/smart-metrics.timer

@@ -0,0 +1,9 @@
+[Unit]
+Description=SMART metrics push every 15 min
+
+[Timer]
+OnBootSec=2min
+OnUnitActiveSec=15min
+
+[Install]
+WantedBy=timers.target