feat(waf): Alerts — Regelübereinstimmungen in DB + UI — v1.2.77

- Migration 0038: waf_alerts-Tabelle
- AlertWriter (Buffered-Channel → async DB-Write)
- SPOE: MatchedRules → sendAlert() nach ProcessRequestHeaders()
- API: GET /waf/alerts + DELETE /waf/alerts
- WAF-Page: Tabs Domains | Alarme; Alarme-Tabelle mit Rule-ID,
  Severity, Aktion (Detected/Blocked), URI, Client-IP + Purge-Button

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/services/waf/waf.go

@@ -113,6 +113,73 @@ func (r *Repo) ListEnabled(ctx context.Context) ([]models.WafConfig, error) {
 	return out, rows.Err()
 }
 
+// WafAlert mirrors the waf_alerts DB row.
+type WafAlert struct {
+	ID        int64      `json:"id"`
+	DomainID  *int64     `json:"domain_id,omitempty"`
+	Hostname  string     `json:"hostname"`
+	ClientIP  string     `json:"client_ip"`
+	Method    string     `json:"method"`
+	URI       string     `json:"uri"`
+	RuleID    int        `json:"rule_id"`
+	RuleMsg   string     `json:"rule_msg"`
+	Severity  string     `json:"severity"`
+	Action    string     `json:"action"`
+	CreatedAt time.Time  `json:"created_at"`
+}
+
+// ListAlerts returns recent WAF alerts, optionally filtered by domain_id.
+func (r *Repo) ListAlerts(ctx context.Context, domainID *int64, limit int) ([]WafAlert, error) {
+	if limit <= 0 || limit > 1000 {
+		limit = 200
+	}
+	var rows interface{ Next() bool; Scan(...any) error; Close(); Err() error }
+	var err error
+	if domainID != nil {
+		rows2, e := r.Pool.Query(ctx, `
+			SELECT id, domain_id, hostname, client_ip, method, uri,
+			       rule_id, rule_msg, severity, action, created_at
+			FROM waf_alerts
+			WHERE domain_id = $1
+			ORDER BY created_at DESC LIMIT $2
+		`, *domainID, limit)
+		rows, err = rows2, e
+	} else {
+		rows2, e := r.Pool.Query(ctx, `
+			SELECT id, domain_id, hostname, client_ip, method, uri,
+			       rule_id, rule_msg, severity, action, created_at
+			FROM waf_alerts
+			ORDER BY created_at DESC LIMIT $1
+		`, limit)
+		rows, err = rows2, e
+	}
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	out := make([]WafAlert, 0, limit)
+	for rows.Next() {
+		var a WafAlert
+		if err := rows.Scan(
+			&a.ID, &a.DomainID, &a.Hostname, &a.ClientIP, &a.Method, &a.URI,
+			&a.RuleID, &a.RuleMsg, &a.Severity, &a.Action, &a.CreatedAt,
+		); err != nil {
+			return nil, err
+		}
+		out = append(out, a)
+	}
+	return out, rows.Err()
+}
+
+// PurgeAlerts removes alerts older than the given number of days.
+func (r *Repo) PurgeAlerts(ctx context.Context, olderThanDays int) error {
+	_, err := r.Pool.Exec(ctx,
+		`DELETE FROM waf_alerts WHERE created_at < NOW() - ($1 || ' days')::interval`,
+		olderThanDays,
+	)
+	return err
+}
+
 // DomainConfigPair combines a domain hostname with its WAF config.
 type DomainConfigPair struct {
 	Hostname string