fix(k3s): 修正磁盘调度 unit 启动命令

systemd 会展开 unit 命令中的百分号 specifier，导致原 oneshot 启动失败。改用 echo 写入调度器，并强制校验 unit 为 active；bash -n、ShellCheck、manual-release-test.sh 通过。

scripts/cluster/configure-control-plane-io.sh

@@ -55,8 +55,8 @@ Before=k3s.service
 
 [Service]
 Type=oneshot
-ExecStart=/bin/sh -c 'printf "%s\\n" mq-deadline > /sys/block/$device/queue/scheduler'
-ExecStop=/bin/sh -c 'printf "%s\\n" none > /sys/block/$device/queue/scheduler'
+ExecStart=/bin/sh -c 'echo mq-deadline > /sys/block/$device/queue/scheduler'
+ExecStop=/bin/sh -c 'echo none > /sys/block/$device/queue/scheduler'
 RemainAfterExit=yes
 
 [Install]
@@ -65,7 +65,9 @@ EOF
     chmod 0644 "$temporary"
     install -o root -g root -m 0644 "$temporary" "$unit_path"
     systemctl daemon-reload
+    systemctl reset-failed "$unit_name" >/dev/null 2>&1 || true
     systemctl enable --now "$unit_name" >/dev/null
+    [[ $(systemctl is-active "$unit_name") == active ]]
     [[ $(current_scheduler) == mq-deadline ]]
     printf 'control_plane_io=APPLIED node=hongkong device=%s scheduler=mq-deadline restart=false\n' "$device"
     ;;