[client] Refactor/iface pkg (#2646)

Refactor the flat code structure

client/iface/iface_ios.go

@@ -0,0 +1,31 @@
+//go:build ios
+
+package iface
+
+import (
+	"fmt"
+
+	"github.com/pion/transport/v3"
+
+	"github.com/netbirdio/netbird/client/iface/bind"
+	"github.com/netbirdio/netbird/client/iface/device"
+)
+
+// NewWGIFace Creates a new WireGuard interface instance
+func NewWGIFace(iFaceName string, address string, wgPort int, wgPrivKey string, mtu int, transportNet transport.Net, args *device.MobileIFaceArguments, filterFn bind.FilterFn) (*WGIface, error) {
+	wgAddress, err := device.ParseWGAddress(address)
+	if err != nil {
+		return nil, err
+	}
+	wgIFace := &WGIface{
+		tun:           device.NewTunDevice(iFaceName, wgAddress, wgPort, wgPrivKey, transportNet, args.TunFd, filterFn),
+		userspaceBind: true,
+	}
+	return wgIFace, nil
+}
+
+// CreateOnAndroid creates a new Wireguard interface, sets a given IP and brings it up.
+// Will reuse an existing one.
+func (w *WGIface) CreateOnAndroid([]string, string, []string) error {
+	return fmt.Errorf("this function has not implemented on this platform")
+}