feat(audit): F1+F2 告警静默规则标记完成 + 审计日志CSV导出实现

F1 告警静默规则 [done]:
- 后端 alert_silence.go: CRUD + Toggle (onetime/daily/weekly 三模式)
- 告警引擎 isSilenced 集成 (alert_engine.go)
- 前端 SilenceRuleTab + SilenceDialog
- 路由 /alerts/silences 已注册

F2 审计日志导出 [done]:
- 重写 ExportAuditLogs: 真正的 CSV 导出 (encoding/csv + UTF-8 BOM)
- 支持 module/action/username/startTime/endTime 筛选
- 导出限制 10000 条防溢出，自动记录审计日志
- JSON 格式向后兼容 (format=json)
- 前端 exportLogs 传递查询参数

同时包含累积的前期工作:
- 目录重构 internal/ -> controller/model/router (v0.55-v0.57)
- 后端分层架构 dto/repository/service/utils
- 审计模块全功能 (终端审计/操作审计/登录日志)
- asciicast v2 录制格式
- SFTP 文件浏览器
- StatStrip 紧凑统计条
- 在线会话自动刷新
- LiveMonitor WebSocket 诊断修复

验证: go build ✅ | npm run build ✅ | Docker 部署 ✅ | 10 回归端点 ✅ | CSV 导出 ✅ | 静默 CRUD ✅

backend/controller/ldap_ou.go

@@ -0,0 +1,122 @@
+package controller
+
+import (
+	"fmt"
+	"net/http"
+	"time"
+
+	"ezops/model"
+
+	"github.com/gin-gonic/gin"
+	"github.com/go-ldap/ldap/v3"
+)
+
+// ListLDAPOUs 列出 LDAP 组织单元
+// POST /api/v1/admin/ldap-config/ou-list
+func (h *LDAPHandler) ListLDAPOUs(c *gin.Context) {
+	var configs []model.LDAPConfig
+	if err := h.db.Order("id").Find(&configs).Error; err != nil || len(configs) == 0 {
+		c.JSON(http.StatusOK, model.Response{Code: 200, Data: []interface{}{}})
+		return
+	}
+	cfg := configs[0]
+	port := 389
+	if cfg.LDAPPort != nil {
+		port = *cfg.LDAPPort
+	}
+
+	conn, err := ldap.DialURL(fmt.Sprintf("ldap://%s:%d", cfg.LDAPHost, port))
+	if err != nil {
+		c.JSON(http.StatusOK, model.Response{Code: 200, Data: []interface{}{}})
+		return
+	}
+	defer conn.Close()
+	conn.SetTimeout(5 * time.Second)
+	if err := conn.Bind(cfg.AdminDN, cfg.AdminPassword); err != nil {
+		c.JSON(http.StatusOK, model.Response{Code: 200, Data: []interface{}{}})
+		return
+	}
+
+	searchReq := ldap.NewSearchRequest(
+		cfg.BaseDN,
+		ldap.ScopeWholeSubtree, ldap.NeverDerefAliases, 0, 0, false,
+		"(objectClass=organizationalUnit)",
+		[]string{"ou", "description"},
+		nil,
+	)
+	sr, err := conn.Search(searchReq)
+	if err != nil {
+		c.JSON(http.StatusOK, model.Response{Code: 200, Data: []interface{}{}})
+		return
+	}
+
+	type OU struct {
+		DN          string `json:"dn"`
+		Name        string `json:"name"`
+		Description string `json:"description"`
+	}
+	var ous []OU
+	for _, e := range sr.Entries {
+		ous = append(ous, OU{
+			DN:          e.DN,
+			Name:        e.GetAttributeValue("ou"),
+			Description: e.GetAttributeValue("description"),
+		})
+	}
+	c.JSON(http.StatusOK, model.Response{Code: 200, Data: ous})
+}
+
+// CreateLDAPOU 创建组织单元
+// POST /api/v1/admin/ldap-config/create-ou
+func (h *LDAPHandler) CreateLDAPOU(c *gin.Context) {
+	var req struct {
+		OUName      string `json:"ou_name"`
+		ParentDN    string `json:"parent_dn"`
+		Description string `json:"description"`
+	}
+	if err := c.ShouldBindJSON(&req); err != nil {
+		c.JSON(http.StatusBadRequest, model.Response{Code: 400, Message: err.Error()})
+		return
+	}
+
+	var configs []model.LDAPConfig
+	if err := h.db.Order("id").Find(&configs).Error; err != nil || len(configs) == 0 {
+		c.JSON(http.StatusBadRequest, model.Response{Code: 400, Message: "LDAP未配置"})
+		return
+	}
+	cfg := configs[0]
+	port := 389
+	if cfg.LDAPPort != nil {
+		port = *cfg.LDAPPort
+	}
+
+	if req.ParentDN == "" {
+		req.ParentDN = cfg.BaseDN
+	}
+	ouDN := fmt.Sprintf("ou=%s,%s", ldap.EscapeFilter(req.OUName), req.ParentDN)
+
+	conn, err := ldap.DialURL(fmt.Sprintf("ldap://%s:%d", cfg.LDAPHost, port))
+	if err != nil {
+		c.JSON(http.StatusInternalServerError, model.Response{Code: 500, Message: "LDAP连接失败: " + err.Error()})
+		return
+	}
+	defer conn.Close()
+	conn.SetTimeout(5 * time.Second)
+	if err := conn.Bind(cfg.AdminDN, cfg.AdminPassword); err != nil {
+		c.JSON(http.StatusInternalServerError, model.Response{Code: 500, Message: "管理员认证失败: " + err.Error()})
+		return
+	}
+
+	addReq := ldap.NewAddRequest(ouDN, nil)
+	addReq.Attribute("objectClass", []string{"organizationalUnit", "top"})
+	addReq.Attribute("ou", []string{req.OUName})
+	if req.Description != "" {
+		addReq.Attribute("description", []string{req.Description})
+	}
+	if err := conn.Add(addReq); err != nil {
+		c.JSON(http.StatusInternalServerError, model.Response{Code: 500, Message: "创建OU失败: " + err.Error()})
+		return
+	}
+
+	c.JSON(http.StatusOK, model.Response{Code: 200, Message: "OU创建成功", Data: gin.H{"dn": ouDN}})
+}