feat: HA-Cluster v1.2.x — Split-Brain, TOTP, Enterprise-FW, Drift-Fix, VIP-Recovery

- keepalived: pg_role='standby' hat Vorrang vor role für BACKUP-Bestimmung
- keepalived-master.sh: gecrasht Dienste beim MASTER-Übergang starten (nicht nur reload)
- confighash: ip_addresses per Interface-Name hashen statt per FK (Cross-Node-Drift-Fix)
- TOTP/2FA: RFC 6238 — Setup-Flow, QR-Code, Admin-Disable; two-step Login
- Firewall-UI: Enterprise-Design — auto-Beschreibung, icon-only Actions, zero-hit Indikator
- fe80-Filter: Link-local IPv6 aus NTP/DNS Listen-Dropdowns entfernen
- VIP-Dashboard, Dual-Path VRRP, GW-Tracking (Migrations 0033/0034)
- Forward Proxy + DNS erweiterte Einstellungen (Migrations 0031/0032)
- unbound-control: edgeguard in unbound-Gruppe via postinst

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

internal/models/forward_proxy_settings.go

@@ -0,0 +1,19 @@
+package models
+
+import "time"
+
+type ForwardProxySettings struct {
+	ID              int       `gorm:"primaryKey"              json:"id"`
+	ListenAddresses string    `gorm:"column:listen_addresses" json:"listen_addresses"`
+	ListenPort      int       `gorm:"column:listen_port"      json:"listen_port"`
+	CacheMemMB      int       `gorm:"column:cache_mem_mb"     json:"cache_mem_mb"`
+	CacheDirMB      int       `gorm:"column:cache_dir_mb"     json:"cache_dir_mb"`
+	MaxObjSizeMB    int       `gorm:"column:max_obj_size_mb"  json:"max_obj_size_mb"`
+	ConnectTimeout  int       `gorm:"column:connect_timeout"  json:"connect_timeout"`
+	ReadTimeout     int       `gorm:"column:read_timeout"     json:"read_timeout"`
+	RequestTimeout  int       `gorm:"column:request_timeout"  json:"request_timeout"`
+	CreatedAt       time.Time `gorm:"column:created_at"       json:"created_at"`
+	UpdatedAt       time.Time `gorm:"column:updated_at"       json:"updated_at"`
+}
+
+func (ForwardProxySettings) TableName() string { return "forward_proxy_settings" }