add primitive AppLinks handler

lib/main.dart

@@ -217,6 +217,13 @@ class _MyHomePageState extends State<MyHomePage> {
   void initState() {
     super.initState();
 
+    final appLinks = AppLinks(); // AppLinks is singleton
+
+    // Subscribe to all events (initial link and further)
+    final sub = appLinks.uriLinkStream.listen((uri) {
+      doSSH("innentuer-open");
+    });
+
     // we do not await generateKey() here, as this is the intended way
     obtainKeyPair();
   }