feat: add mtr support for windows

[Audionut]

Completely LLM'd this.

Requires https://github.com/dqos/WinMTRCmd

No idea what if any issues it causes for linux based systems.

[s0up4200]

We should probably merge this into a new branch, and make a new PR based on that local branch. That way I can pull the docker image to test on my server.

Would also be nice if the README had some info about this dependency for Windows.

[s0up4200]

This makes sense now I guess 🤔 Other than that I cant really say. Looks good to me.

diff --git a/internal/speedtest/packetloss.go b/internal/speedtest/packetloss.go
index 3e0cdf6..b3d996d 100644
--- a/internal/speedtest/packetloss.go
+++ b/internal/speedtest/packetloss.go
@@ -10,6 +10,7 @@ import (
 	"io"
 	"net"
 	"os/exec"
+	"runtime"
 	"strings"
 	"sync"
 	"time"
@@ -993,6 +994,13 @@ type mtrReport struct {
 
 // runMTRTest runs an MTR test and returns statistics
 func (s *PacketLossService) runMTRTest(monitor *PacketLossMonitor) (*probing.Statistics, error) {
+	if _, err := exec.LookPath("mtr"); err != nil {
+		if runtime.GOOS == "windows" {
+			return nil, fmt.Errorf("WinMTRCmd not found: please install from https://github.com/dqos/WinMTRCmd/releases and add to PATH")
+		}
+		return nil, fmt.Errorf("mtr not found: please install mtr package for your system")
+	}
+
 	// Initialize GeoIP databases if not already done
 	// This is a workaround since PacketLossService doesn't have access to the main service
 	if countryDB == nil && asnDB == nil {

[Audionut]

Nice one, added.