Add a way of showing messages (info, error, warning...) to users.

[AlbertoCasasOrtiz]

While addressing the record mp4 videos, I noticed we have no way of notifying users when something happens (error, info, warning...).

I think a good approach, similar to what we do in opencap and addbiomechanics, would be to implement toast notifications. This is how to do this in react using the mui library:

https://mui.com/material-ui/react-snackbar/

[AlbertoCasasOrtiz]

This is working in #113. In the end, I am using notistack. Notistack API Reference: https://notistack.com/api-reference