Add the ability to set current session as read-only

[SeaDve]

First of all, thanks for the wonderful app! I found it helpful and use it almost daily for taking down school notes.

Is your feature request related to a problem? Please describe.
Sometimes I'd like to just browse the notes and I'd like to avoid writing something accidentally.

Describe the solution you'd like
There could be a button beside the Focus Mode button that temporarily disables editing and hides all the toolbar (like in Focus Mode).

Describe alternatives you've considered
An alternative is to export it, but I would lose the vertical continuity of the document.

[flxzt]

Thank you for your kind words :)

Yes agreed, that would be a nice improvement. I am not yet sure if we should add this as a button in the top bar or if it should be an item in the canvas menu. On the one hand it would probably be a often used feature and should be displayed somewhere prominently but I also don't want to clutter the base UI more than necessary.