[client] Refactor/iface pkg (#2646)

Refactor the flat code structure

client/iface/iface_destroy_linux.go

@@ -0,0 +1,22 @@
+//go:build linux && !android
+
+package iface
+
+import (
+	"fmt"
+
+	"github.com/vishvananda/netlink"
+)
+
+func (w *WGIface) Destroy() error {
+	link, err := netlink.LinkByName(w.Name())
+	if err != nil {
+		return fmt.Errorf("failed to get link by name %s: %w", w.Name(), err)
+	}
+
+	if err := netlink.LinkDel(link); err != nil {
+		return fmt.Errorf("failed to delete link %s: %w", w.Name(), err)
+	}
+
+	return nil
+}