Add an error when attempting to invoke "Add Memory Region" on a raw view

[emesare]

Screen.Recording.2026-03-03.at.8.12.00.AM.mov

We do not support adding memory regions in raw views, since the raw view is the only constructed view when making a new file, it may be confusing experience if the user is used to using the "Add Memory Region" action, which works for every view type except raw view.

Maybe instead of not allowing "Add Memory Region" we should either add a default mapped view to the "New File" or we should make raw view support memory regions.