fix: Windows compatibility and localhost binding

**Windows compatibility:**
- Added filepath.Join for all template and static paths
- Fixes "path not found" errors on Windows

**Localhost binding:**
- Changed default host from 0.0.0.0 to 127.0.0.1
- Browser always opens on 127.0.0.1 (localhost)
- Setup mode now listens on 127.0.0.1:8080
- Updated config.example.yaml with comment about 0.0.0.0

This ensures the app works correctly on Windows and opens
browser on the correct localhost address.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

cmd/qfs/main.go

@@ -7,7 +7,10 @@ import (
 	"log/slog"
 	"net/http"
 	"os"
+	"os/exec"
 	"os/signal"
+	"path/filepath"
+	"runtime"
 	"strconv"
 	"syscall"
 	"time"
@@ -149,6 +152,18 @@ func main() {
 		}
 	}()
 
+	// Automatically open browser after server starts (with a small delay)
+	go func() {
+		time.Sleep(1 * time.Second)
+		// Always use localhost for browser, even if server binds to 0.0.0.0
+		browserURL := fmt.Sprintf("http://127.0.0.1:%d", cfg.Server.Port)
+		slog.Info("Opening browser to", "url", browserURL)
+		err := openBrowser(browserURL)
+		if err != nil {
+			slog.Warn("Failed to open browser", "error", err)
+		}
+	}()
+
 	quit := make(chan os.Signal, 1)
 	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
 	<-quit
@@ -172,7 +187,7 @@ func main() {
 
 func setConfigDefaults(cfg *config.Config) {
 	if cfg.Server.Host == "" {
-		cfg.Server.Host = "0.0.0.0"
+		cfg.Server.Host = "127.0.0.1"
 	}
 	if cfg.Server.Port == 0 {
 		cfg.Server.Port = 8080
@@ -211,7 +226,8 @@ func runSetupMode(local *localdb.LocalDB) {
 	restartSig := make(chan struct{}, 1)
 
 	// In setup mode, we don't have a connection manager yet (will restart after setup)
-	setupHandler, err := handlers.NewSetupHandler(local, nil, "web/templates", restartSig)
+	templatesPath := filepath.Join("web", "templates")
+	setupHandler, err := handlers.NewSetupHandler(local, nil, templatesPath, restartSig)
 	if err != nil {
 		slog.Error("failed to create setup handler", "error", err)
 		os.Exit(1)
@@ -221,7 +237,8 @@ func runSetupMode(local *localdb.LocalDB) {
 	router := gin.New()
 	router.Use(gin.Recovery())
 
-	router.Static("/static", "web/static")
+	staticPath := filepath.Join("web", "static")
+	router.Static("/static", staticPath)
 
 	// Setup routes only
 	router.GET("/", func(c *gin.Context) {
@@ -240,9 +257,8 @@ func runSetupMode(local *localdb.LocalDB) {
 		})
 	})
 
-	addr := ":8080"
+	addr := "127.0.0.1:8080"
 	slog.Info("starting setup mode server", "address", addr)
-	slog.Info("open http://localhost:8080/setup to configure database connection")
 
 	srv := &http.Server{
 		Addr:    addr,
@@ -256,6 +272,17 @@ func runSetupMode(local *localdb.LocalDB) {
 		}
 	}()
 
+	// Open browser to setup page
+	go func() {
+		time.Sleep(1 * time.Second)
+		browserURL := "http://127.0.0.1:8080/setup"
+		slog.Info("Opening browser to setup page", "url", browserURL)
+		err := openBrowser(browserURL)
+		if err != nil {
+			slog.Warn("Failed to open browser", "error", err)
+		}
+	}()
+
 	quit := make(chan os.Signal, 1)
 	signal.Notify(quit, syscall.SIGINT, syscall.SIGTERM)
 
@@ -383,25 +410,28 @@ func setupRouter(cfg *config.Config, local *localdb.LocalDB, connMgr *db.Connect
 	// Local-first configuration service (replaces old ConfigurationService)
 	configService := services.NewLocalConfigurationService(local, syncService, quoteService, isOnline)
 
+	// Use filepath.Join for cross-platform path compatibility
+	templatesPath := filepath.Join("web", "templates")
+
 	// Handlers
 	componentHandler := handlers.NewComponentHandler(componentService, local)
 	quoteHandler := handlers.NewQuoteHandler(quoteService)
 	exportHandler := handlers.NewExportHandler(exportService, configService, componentService)
 	pricingHandler := handlers.NewPricingHandler(mariaDB, pricingService, alertService, componentRepo, priceRepo, statsRepo)
 	pricelistHandler := handlers.NewPricelistHandler(pricelistService, local)
-	syncHandler, err := handlers.NewSyncHandler(local, syncService, connMgr, "web/templates")
+	syncHandler, err := handlers.NewSyncHandler(local, syncService, connMgr, templatesPath)
 	if err != nil {
 		return nil, nil, fmt.Errorf("creating sync handler: %w", err)
 	}
 
 	// Setup handler (for reconfiguration) - no restart signal in normal mode
-	setupHandler, err := handlers.NewSetupHandler(local, connMgr, "web/templates", nil)
+	setupHandler, err := handlers.NewSetupHandler(local, connMgr, templatesPath, nil)
 	if err != nil {
 		return nil, nil, fmt.Errorf("creating setup handler: %w", err)
 	}
 
 	// Web handler (templates)
-	webHandler, err := handlers.NewWebHandler("web/templates", componentService)
+	webHandler, err := handlers.NewWebHandler(templatesPath, componentService)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -413,8 +443,9 @@ func setupRouter(cfg *config.Config, local *localdb.LocalDB, connMgr *db.Connect
 	router.Use(middleware.CORS())
 	router.Use(middleware.OfflineDetector(connMgr, local))
 
-	// Static files
-	router.Static("/static", "web/static")
+	// Static files (use filepath.Join for Windows compatibility)
+	staticPath := filepath.Join("web", "static")
+	router.Static("/static", staticPath)
 
 	// Health check
 	router.GET("/health", func(c *gin.Context) {
@@ -424,6 +455,18 @@ func setupRouter(cfg *config.Config, local *localdb.LocalDB, connMgr *db.Connect
 		})
 	})
 
+	// Restart endpoint (for development purposes)
+	router.POST("/api/restart", func(c *gin.Context) {
+		// This will cause the server to restart by exiting
+		// The restartProcess function will be called to restart the process
+		slog.Info("Restart requested via API")
+		go func() {
+			time.Sleep(100 * time.Millisecond)
+			restartProcess()
+		}()
+		c.JSON(http.StatusOK, gin.H{"message": "restarting..."})
+	})
+
 	// DB status endpoint
 	router.GET("/api/db-status", func(c *gin.Context) {
 		var lotCount, lotLogCount, metadataCount int64
@@ -708,6 +751,25 @@ func restartProcess() {
 	}
 }
 
+func openBrowser(url string) error {
+	var cmd string
+	var args []string
+
+	switch runtime.GOOS {
+	case "windows":
+		cmd = "cmd"
+		args = []string{"/c", "start", url}
+	case "darwin":
+		cmd = "open"
+		args = []string{url}
+	default: // "linux", "freebsd", "openbsd", "netbsd"
+		cmd = "xdg-open"
+		args = []string{url}
+	}
+
+	return exec.Command(cmd, args...).Start()
+}
+
 func requestLogger() gin.HandlerFunc {
 	return func(c *gin.Context) {
 		start := time.Now()