Give user alert to confirm browser refresh

[karthick-murugan]

Fixes #81

This PR addresses #81 – Give user alert to confirm browser refresh by adding a browser-level confirmation dialog that triggers when a user attempts to refresh or close the Playground window/tab. This helps prevent accidental data loss or session interruption due to unintended refreshes.

✅ Changes Introduced

• Added a beforeunload event listener to the Playground UI.
• The event prompts a native browser confirmation dialog, asking the user to confirm if they really want to refresh or navigate away from the page.
• Ensures smoother UX by reducing unintentional disruptions during usage.

🧪 Testing Instructions

• Start the Playground.
• Interact with any UI component to simulate an active session.
• Try refreshing the page or closing the browser tab.
• A browser-native alert will now ask for confirmation.

Sceenshot