feat: 完成附件存储重构与磁盘监控功能，同步物料档案与入库单规则更新

1.  新增跨平台磁盘空间监控能力，每日7点自动检测附件目录剩余空间，触发阈值告警
2.  重构附件存储方案为年/月/日/文件类型分层结构，统一MES与WMS的附件管理逻辑
3.  对齐物料档案与入库单的质量状态校验规则，仅合格品计入库存与出库
4.  实现入库单作废功能与区域库位的多级父子结构管理
5.  删除物料简称字段，补充规格型号与单位必填项，统一系统数据口径
6.  新增附件中心与磁盘状态查询接口，完善权限控制与操作日志

bj_power_mes/internal/handler/attachment_monitor.go

@@ -0,0 +1,105 @@
+package handler
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"os"
+	"time"
+
+	"bj_power_mes/common/httpx"
+	"bj_power_mes/internal/svc"
+
+	"github.com/zeromicro/go-zero/core/logx"
+)
+
+// diskStatusView 磁盘空间状态视图（附件中心顶部提示 + 定时告警共用）。
+type diskStatusView struct {
+	RootDir     string `json:"rootDir"`
+	UsedPercent int    `json:"usedPercent"`
+	FreeBytes   uint64 `json:"freeBytes"`
+	TotalBytes  uint64 `json:"totalBytes"`
+	WarnPercent int    `json:"warnPercent"`
+	CritPercent int    `json:"critPercent"`
+	Level       string `json:"level"` // ok / warn / critical / unknown
+	Message     string `json:"message"`
+	CheckedAt   int64  `json:"checkedAt"`
+}
+
+// diskStatus 读取附件根目录所在磁盘剩余空间并给出告警级别。
+// 剩余 < DiskCriticalPercent → critical（提示执行备份归档清理）；< DiskWarnPercent → warn。
+func diskStatus(svcCtx *svc.ServiceContext) diskStatusView {
+	cfg := svcCtx.Config.Upload
+	root := cfg.Dir
+	if root == "" {
+		root = "uploads"
+	}
+	v := diskStatusView{
+		RootDir: root, WarnPercent: cfg.DiskWarnPercent, CritPercent: cfg.DiskCriticalPercent,
+		Level: "ok", Message: "磁盘空间正常", CheckedAt: time.Now().Unix(),
+	}
+	used, free, total, err := diskUsage(root)
+	if err != nil {
+		_ = os.MkdirAll(root, 0o755)
+		used, free, total, err = diskUsage(root)
+	}
+	if err != nil {
+		v.Level = "unknown"
+		v.Message = "磁盘空间检测失败：" + err.Error()
+		return v
+	}
+	v.UsedPercent, v.FreeBytes, v.TotalBytes = used, free, total
+	freePercent := 100 - used
+	switch {
+	case freePercent < cfg.DiskCriticalPercent:
+		v.Level = "critical"
+		v.Message = fmt.Sprintf("磁盘剩余空间仅 %d%%，低于 %d%%，请立即执行备份归档清理（附件中心可一键归档）", freePercent, cfg.DiskCriticalPercent)
+	case freePercent < cfg.DiskWarnPercent:
+		v.Level = "warn"
+		v.Message = fmt.Sprintf("磁盘剩余空间 %d%%，低于 %d%% 告警线，请及时清理", freePercent, cfg.DiskWarnPercent)
+	}
+	return v
+}
+
+// DiskStatusHandler GET /attachment/disk-status
+func DiskStatusHandler(svcCtx *svc.ServiceContext) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		httpx.Ok(w, diskStatus(svcCtx))
+	}
+}
+
+// StartDiskMonitor 启动磁盘空间监控：每天 DiskCheckHour(默认 7 点) 检测一次，
+// 剩余 <20% 告警、<10% 提示清理（写服务日志 + 操作日志，附件中心顶部同步展示）。
+func StartDiskMonitor(svcCtx *svc.ServiceContext) {
+	go func() {
+		hour := svcCtx.Config.Upload.DiskCheckHour
+		if hour < 0 || hour > 23 {
+			hour = 7
+		}
+		for {
+			now := time.Now()
+			next := time.Date(now.Year(), now.Month(), now.Day(), hour, 0, 0, 0, time.Local)
+			if !next.After(now) {
+				next = next.Add(24 * time.Hour)
+			}
+			time.Sleep(time.Until(next))
+			checkDiskOnce(svcCtx)
+		}
+	}()
+}
+
+func checkDiskOnce(svcCtx *svc.ServiceContext) {
+	st := diskStatus(svcCtx)
+	switch st.Level {
+	case "critical":
+		logx.Errorf("[磁盘监控] %s（已用 %d%%，剩余 %d%%）", st.Message, st.UsedPercent, 100-st.UsedPercent)
+		svcCtx.EventLog.Write(context.Background(), "system.disk", "", "system", "attachment", "disk", st.Message,
+			map[string]any{"usedPercent": st.UsedPercent, "freeBytes": st.FreeBytes})
+	case "warn":
+		logx.Alert("[磁盘监控] " + st.Message)
+		svcCtx.EventLog.Write(context.Background(), "system.disk", "", "system", "attachment", "disk", st.Message,
+			map[string]any{"usedPercent": st.UsedPercent, "freeBytes": st.FreeBytes})
+	default:
+		logx.Infof("[磁盘监控] 正常：剩余 %d%%（%s）", 100-st.UsedPercent, st.RootDir)
+	}
+}