Add notification feature to backup scripts for various services

Enhance backup scripts for Nextcloud, Gitea, Paperless, Vaultwarden, Immich, and VPS configurations by adding Telegram notifications upon completion. Include details such as backup size and objects backed up. Update backup documentation to reflect these changes and ensure clarity on backup processes and retention policies.

scripts/backup-vps-mtproto.sh

@@ -37,6 +37,18 @@ ssh "${SSH_OPTS[@]}" "${VPS_USER}@${VPS_HOST}" "tar -chzf - -C / \
   var/www/katykhin.store" > "$ARCHIVE"
 
 chmod 600 "$ARCHIVE"
-echo "Бэкап MTProto (VPS DE): $ARCHIVE ($(du -h "$ARCHIVE" | cut -f1))"
+echo "Бэкап MTProto (VPS DE): $ARCHIVE ($(du --apparent-size -h "$ARCHIVE" | cut -f1))"
 
 find "$BACKUP_ROOT" -name 'mtproto-config-*.tar.gz' -mtime +$RETENTION_DAYS -delete
+
+NOTIFY_SCRIPT="${NOTIFY_SCRIPT:-/root/scripts/notify-telegram.sh}"
+if [ -x "$NOTIFY_SCRIPT" ]; then
+  SIZE=$(du --apparent-size -h "$ARCHIVE" | cut -f1)
+  SIZE_BYTES=$(stat -c%s "$ARCHIVE" 2>/dev/null || echo 0)
+  BODY="Резервное копирование завершено.
+Объекты: конфиги MTProto, nginx, Let's Encrypt, сайт (VPS DE).
+Размер копии: ${SIZE}."
+  [ "$SIZE_BYTES" -lt 1024 ] 2>/dev/null && BODY="${BODY}
+⚠️ Подозрительно малый размер — проверьте SSH и наличие файлов на VPS."
+  "$NOTIFY_SCRIPT" "🌐 VPS MTProto (DE)" "$BODY" || true
+fi