feat: implement security, discovery, history, file transfer, web UI (P0-P3)

internal/notify/notify_linux.go

@@ -0,0 +1,15 @@
+//go:build linux
+
+package notify
+
+import "os/exec"
+
+// Notifier uses notify-send (libnotify) on Linux.
+type notifier struct{}
+
+// New returns a Linux notifier using notify-send.
+func New() Notifier { return notifier{} }
+
+func (notifier) Notify(title, body string) error {
+	return exec.Command("notify-send", title, body).Run()
+}