Feat/Fix: re-embed app on pop-out window close and prevent duplicate app view

[yaseminozkut]

• Fixes issue Pop-out app window: no re-embedding on close and double view bug #263
• When the pop-out window is closed by the user while the app is still running, the app is automatically re-embedded into the right panel.
• When the pop-out window is opened, the open button is replaced by "Viewing in separate window" text. This will prevent users clicking "Open" button again and open a duplicate view of the same app.

Now when user pops out the window the app card looks like:

Note: tested on simulation + MacOS
Note: I did not remove the "Open" button codes from the project file but I believe that is now redundant. I'm not sure if there can be another use case for that button or if its still needed.