feat: 监控告警体系统一重构 + 自动化任务调度引擎 + 监控大屏拆分

告警中心
- 新增统一告警(alert_unified)、监控告警规则(monitor_alert_rule)、指标目录(alert_metric_catalog)
- 通知策略与消息分发(alert_notify_policy/dispatch/message)、静默规则
- 告警引擎按阈值/SNMP 拆分(alert_engine_monitor/snmp)

监控采集
- SNMP 常量/模板与历史指标(snmp templates/constants、snmp_metrics_history、snmp_collect)
- 中间件监控 Redis 采集与种子(middleware_monitor_redis/seed)
- 站点探测 pkg(siteprobe) + 站点视图(site_view)

自动化任务
- cron 调度器(cronscheduler)、脚本运行器(scriptrunner)、系统任务(systask)及运行记录(cron_job_run、system_task)

审计与凭证
- 审计设置(audit_setting) + 历史清理(auditcleaner)

前端
- 监控页面(host/middleware/site/snmp)拆分为子模块并大屏化
- 告警中心多 Tab(规则/指标目录/通知策略/静默)、任务管理组件重构、Agent CLI Markdown 渲染
- 移除旧脚本卡片/详情/日志组件，统一为 ScriptTable/ScriptCodeEditor/TerminalOutput

Co-Authored-By: Claude <noreply@anthropic.com>

backend/pkg/siteprobe/ssl.go

@@ -0,0 +1,108 @@
+package siteprobe
+
+import (
+	"context"
+	"crypto/tls"
+	"crypto/x509"
+	"fmt"
+	"net"
+	"net/url"
+	"strings"
+	"time"
+
+	"ezops/model"
+)
+
+// parseSSLTarget 解析 SSL 拨测地址，支持 example.com:443 / https://example.com // Logan.Li
+func parseSSLTarget(raw string) (host, port string, err error) {
+	raw = strings.TrimSpace(raw)
+	if raw == "" {
+		return "", "", fmt.Errorf("SSL 地址不能为空")
+	}
+	lower := strings.ToLower(raw)
+	// 兼容 https:example.com（单斜杠写法）
+	if strings.HasPrefix(lower, "https:") && !strings.HasPrefix(lower, "https://") {
+		raw = "https://" + strings.TrimSpace(raw[len("https:"):])
+		lower = strings.ToLower(raw)
+	}
+	if strings.HasPrefix(lower, "http://") || strings.HasPrefix(lower, "https://") || strings.HasPrefix(lower, "ssl://") {
+		u, parseErr := url.Parse(raw)
+		if parseErr != nil || u.Host == "" {
+			return "", "", fmt.Errorf("SSL 地址格式无效: %s", raw)
+		}
+		if h, p, splitErr := net.SplitHostPort(u.Host); splitErr == nil {
+			return h, p, nil
+		}
+		defPort := "443"
+		if u.Scheme == "http" {
+			defPort = "80"
+		}
+		return u.Hostname(), defPort, nil
+	}
+	// 去掉路径后缀，如 example.com:443/foo
+	if idx := strings.Index(raw, "/"); idx >= 0 {
+		raw = raw[:idx]
+	}
+	return splitHostPort(raw, "443")
+}
+
+// probeSSL 纯 TLS 握手检测证书（不发起 HTTP 请求）// Logan.Li
+func probeSSL(ctx context.Context, task model.SiteTask) ProbeOutcome {
+	start := time.Now()
+	host, port, err := parseSSLTarget(task.URL)
+	if err != nil {
+		return failOutcome(start, err.Error())
+	}
+	addr := net.JoinHostPort(host, port)
+	d := &net.Dialer{Timeout: time.Until(deadlineFromCtx(ctx))}
+	conn, err := tls.DialWithDialer(d, "tcp", addr, &tls.Config{
+		ServerName:         host,
+		InsecureSkipVerify: !task.VerifySSL,
+	})
+	elapsed := msSince(start)
+	if err != nil {
+		if ctx.Err() == context.DeadlineExceeded {
+			return ProbeOutcome{Status: model.SiteResultTimeout, TotalTime: elapsed, ResponseTime: elapsed, ErrorMessage: "TLS 握手超时"}
+		}
+		return failOutcome(start, fmt.Sprintf("TLS 握手失败: %s", err.Error()))
+	}
+	defer conn.Close()
+
+	remote := ""
+	if addr := conn.RemoteAddr(); addr != nil {
+		remote = addr.String()
+	}
+	out := ProbeOutcome{
+		Status:       model.SiteResultSuccess,
+		ResponseTime: elapsed,
+		TotalTime:    elapsed,
+		RemoteIP:     remote,
+	}
+	applyCertsToOutcome(&out, conn.ConnectionState().PeerCertificates)
+	return out
+}
+
+// applyCertsToOutcome 从 TLS 证书链填充到期信息 // Logan.Li
+func applyCertsToOutcome(out *ProbeOutcome, certs []*x509.Certificate) {
+	if len(certs) == 0 {
+		return
+	}
+	cert := certs[0]
+	expiry := cert.NotAfter
+	days := int(time.Until(expiry).Hours() / 24)
+	out.SSLCertExpiry = &expiry
+	out.SSLDaysRemaining = days
+	out.SSLCertIssuer = cert.Issuer.CommonName
+	if out.SSLCertIssuer == "" {
+		out.SSLCertIssuer = cert.Issuer.String()
+	}
+	out.SSLCertSubject = cert.Subject.CommonName
+	if out.SSLCertSubject == "" {
+		out.SSLCertSubject = cert.Subject.String()
+	}
+}
+
+// IsSSLProbeTask 是否为 SSL 证书拨测任务 // Logan.Li
+func IsSSLProbeTask(task model.SiteTask) bool {
+	return strings.EqualFold(string(task.TaskType), "ssl")
+}