feat: add Wine Z: path prefix for Windows platform on Linux host

- Add winePath helper that prepends Z: when platform is windows on Linux
- Thread platform through buildModPath, buildAutoArgs, and Start()
- Apply Z: prefix to -config=, -mod=, -profiles=, and %command% binary paths
- Add tests for winePath, buildAutoArgs, and buildModPath with platform param
- Fix formatting across services package with gofmt
- Include all prior bug fixes from this branch

backend/cmd/server/main.go

@@ -57,9 +57,11 @@ func main() {
 
 	r := gin.Default()
 
+	frontendServed := false
 	subFS, subErr := fs.Sub(embed.Frontend, "dist")
 	if subErr == nil {
 		if _, err := subFS.Open("index.html"); err == nil {
+			frontendServed = true
 			r.NoRoute(func(c *gin.Context) {
 				path := strings.TrimPrefix(c.Request.URL.Path, "/")
 				if path == "" {
@@ -81,7 +83,7 @@ func main() {
 		}
 	}
 
-	handler := api.New(settings, configMgr, modlistMgr, process, steamcmd, scheduler, streamer, dataDir, serverfileDir, modsDir, cfgDir, profilesDir)
+	handler := api.New(settings, configMgr, modlistMgr, process, steamcmd, scheduler, streamer, dataDir, serverfileDir, modsDir, cfgDir, profilesDir, frontendServed)
 	handler.SetupRoutes(r)
 
 	// Startup auto-tasks