cmd/tsconnect: enable web links addon in the terminal

More user friendly, and as a side-effect we handle SSH check mode better,
since the URL that's output is now clickable.

Fixes #5247

Signed-off-by: Mihai Parparita <mihai@tailscale.com>

cmd/tsconnect/src/app/app.tsx

@@ -92,6 +92,12 @@ class App extends Component<{}, AppState> {
   }
 
   handleBrowseToURL = (url: string) => {
+    if (this.state.ipnState === "Running") {
+      // Ignore URL requests if we're already running -- it's most likely an
+      // SSH check mode trigger and we already linkify the displayed URL
+      // in the terminal.
+      return
+    }
     this.setState({ browseToURL: url })
   }