all: watch lease files if send client info enabled

So users who run ctrld in Linux can still see clients info, even though
it's not an router platform that ctrld supports.

internal/router/router.go

@@ -7,11 +7,9 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
-	"sync"
 	"sync/atomic"
 	"time"
 
-	"github.com/fsnotify/fsnotify"
 	"github.com/kardianos/service"
 	"tailscale.com/logtail/backoff"
 
@@ -38,8 +36,6 @@ var routerPlatform atomic.Pointer[router]
 type router struct {
 	name           string
 	sendClientInfo bool
-	mac            sync.Map
-	watcher        *fsnotify.Watcher
 }
 
 // IsSupported reports whether the given platform is supported by ctrld.
@@ -102,16 +98,6 @@ func Configure(c *ctrld.Config) error {
 		if c.HasUpstreamSendClientInfo() {
 			r := routerPlatform.Load()
 			r.sendClientInfo = true
-			watcher, err := fsnotify.NewWatcher()
-			if err != nil {
-				return err
-			}
-			r.watcher = watcher
-			go r.watchClientInfoTable()
-			for file, readClienInfoFunc := range clientInfoFiles {
-				_ = readClienInfoFunc(file)
-				_ = r.watcher.Add(file)
-			}
 		}
 		configure := configureFunc[name]
 		if err := configure(); err != nil {