feat: add host flag to configure web UI listen address

Co-authored-by: Copilot <copilot@github.com>

cmd/client/main.go

@@ -15,6 +15,7 @@ import (
 func main() {
 	dataDir := flag.String("data-dir", "./thefeeddata", "Data directory for config, cache, and sessions")
 	port := flag.Int("port", 8080, "Web UI port")
+	host := flag.String("host", "127.0.0.1", "Web UI listen address (host), use 0.0.0.0 to expose to LAN")
 	password := flag.String("password", "", "Admin password for web UI (empty = no auth)")
 	showVersion := flag.Bool("version", false, "Show version and exit")
 	flag.Usage = func() {
@@ -28,13 +29,19 @@ func main() {
 		os.Exit(0)
 	}
 
-	srv, err := web.New(*dataDir, *port, *password)
+	srv, err := web.New(*dataDir, *port, *host, *password)
 	if err != nil {
 		log.Fatalf("Failed to start: %v", err)
 	}
 
 	// Try to open browser automatically
-	url := fmt.Sprintf("http://127.0.0.1:%d", *port)
+
+	// Open browser on the chosen host (localhost if default)
+	browserHost := *host
+	if browserHost == "0.0.0.0" {
+		browserHost = "127.0.0.1"
+	}
+	url := fmt.Sprintf("http://%s:%d", browserHost, *port)
 	go openBrowser(url)
 
 	if err := srv.Run(); err != nil {