add toast for extension update availability

[bachig26]

Describe your suggested feature

Expected Behaviour:

In startup or when the Extension Repo refreshes for checking the new update, a toast to notify would be an great addition.

also if added, it needs to suppressed while in the video player.

Edit: also if an new extension is added too.

Acknowledgements

• [X] I have searched the existing issues and this is a new ticket, NOT a duplicate or related to another open issue.