docs: update startup message to mention WebUI

- Changed "Server running at" to "Server and WebUI running at"
- Clarifies that the web interface is available at the same port

src/index.js

@@ -71,7 +71,7 @@ app.listen(PORT, () => {
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-${border}  ${align(`Server running at: http://localhost:${PORT}`)}${border}
+${border}  ${align(`Server and WebUI running at: http://localhost:${PORT}`)}${border}
 ${statusSection}║                                                              ║
 ${controlSection}
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