chore: 初始开源发布

iotlcm-admin-svr：管理后台服务。

- Go module：iotlcm → git.5iot.com/iotlcm-public/iotlcm-admin-svr（729 文件）
- 凭据与地址脱敏：JWT signingKey（含代码里的 MustGet 默认值）、
  MySQL DSN、Redis 口令、告警邮件发件人邮箱全部改为占位；
  私网 IP → 文档地址段；库名 xiujie_admin → iotlcm
- 真实手机号/邮箱 → 合法 11 位编造号 / example.com
- 移除内部资产：CI 触发器、过时 DDL（sql/db_iotlcm.sql）、
  私有依赖 go get 行、明文 registry 登录口令
- 启动 banner 统一 IOTLCM 方块字 + 社区惯例署名
- Dockerfile 改用公共基础镜像
- 拼错的 RADEME.md → README.md，README 重写
- 需要真实数据库的用例改为可用 IOTLCM_TEST_WITH_DB=1 显式启用
- 补 Apache-2.0 LICENSE，LF 行尾 + .gitattributes

数据库 schema 不随本仓发布（生产 DDL 已过时），README 已说明。

server/utility/iot_excelize/local_storage.go

@@ -0,0 +1,89 @@
+package iot_excelize
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"strings"
+	"time"
+
+	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/consts"
+	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/model"
+	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/model/entity"
+	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/service"
+	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/utility/uuid32"
+
+	"github.com/xuri/excelize/v2"
+)
+
+// SaveLocal saves an Excel workbook through SysOss local storage and records it
+// in the sys_oss table.
+func SaveLocal(ctx context.Context, f *excelize.File, fileName string, category string) (*entity.SysOss, error) {
+	if category == "" {
+		category = "export"
+	}
+	category = safePathName(category)
+	if fileName == "" {
+		fileName = "excel"
+	}
+
+	fileName = uniqueExcelFileName(fileName)
+	reader, err := ToReadSeeker(f)
+	if err != nil {
+		return nil, err
+	}
+	if _, err = reader.Seek(0, io.SeekStart); err != nil {
+		return nil, err
+	}
+	content, err := io.ReadAll(reader)
+	if err != nil {
+		return nil, err
+	}
+
+	result, err := service.SysOss().SaveContent(ctx, &model.SysOssSaveContentParam{
+		Content:     content,
+		FileName:    fileName,
+		NewFileType: consts.SysUploadNewFileTypeUserFile,
+		SubDirName:  "excel/" + category,
+		NotAddDate:  0,
+	})
+	if err != nil {
+		return nil, err
+	}
+	if result == nil {
+		return nil, nil
+	}
+	return result.SysOss, nil
+}
+
+func safeExcelFileName(fileName string) string {
+	fileName = strings.TrimSpace(fileName)
+	if fileName == "" {
+		fileName = "excel"
+	}
+	fileName = strings.TrimSuffix(fileName, ".xlsx")
+	for _, old := range []string{"\\", "/", ":", "*", "?", "\"", "<", ">", "|"} {
+		fileName = strings.ReplaceAll(fileName, old, "_")
+	}
+	return fileName + ".xlsx"
+}
+
+func uniqueExcelFileName(fileName string) string {
+	fileName = strings.TrimSuffix(safeExcelFileName(fileName), ".xlsx")
+	uid := uuid32.S()
+	if len(uid) > 8 {
+		uid = uid[:8]
+	}
+	return fmt.Sprintf("%s_%s_%s.xlsx", time.Now().Format("20060102150405000"), uid, fileName)
+}
+
+func safePathName(name string) string {
+	name = strings.TrimSpace(name)
+	if name == "" {
+		return "export"
+	}
+	for _, old := range []string{"\\", "/", ":", "*", "?", "\"", "<", ">", "|", "."} {
+		name = strings.ReplaceAll(name, old, "_")
+	}
+	return name
+}