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/firewall/firewall.go

@@ -363,11 +363,24 @@ func (g *Generator) loadAutoRules(ctx context.Context) []AutoFWRule {
 		}
 	}
 
-	// Squid Forward-Proxy: wenn ≥1 aktive ACL → tcp 3128 inbound
-	// (squid bindet aktuell 0.0.0.0:3128, daher kein DstIP-Filter).
-	var aclCount int
-	if err := g.Pool.QueryRow(ctx, `SELECT count(*) FROM forward_proxy_acls WHERE active`).Scan(&aclCount); err == nil && aclCount > 0 {
-		out = append(out, AutoFWRule{Proto: "tcp", Port: 3128, Comment: "Forward-Proxy (Squid)"})
+	// Squid Forward-Proxy: lese Port + Listen-Adressen aus
+	// forward_proxy_settings. Für jede nicht-loopback IP eine
+	// Auto-Rule; leere Liste = alle Interfaces (generische Regel).
+	var squidAddrs string
+	var squidPort int
+	if err := g.Pool.QueryRow(ctx,
+		`SELECT listen_addresses, listen_port FROM forward_proxy_settings WHERE id=1`,
+	).Scan(&squidAddrs, &squidPort); err == nil && squidPort > 0 {
+		addrs := splitCSV(squidAddrs)
+		if len(addrs) == 0 {
+			out = append(out, AutoFWRule{Proto: "tcp", Port: squidPort, Comment: "Forward-Proxy (Squid)"})
+		} else {
+			for _, ip := range addrs {
+				if !isLoopback(ip) {
+					out = append(out, AutoFWRule{Proto: "tcp", Port: squidPort, DstIP: ip, Comment: "Forward-Proxy (Squid) auf " + ip})
+				}
+			}
+		}
 	}
 
 	// WireGuard server-mode: udp <listen_port> pro aktive iface.