Add Inbox feature to mobile clients

I'm an iOS user, but I think this feature should be added to the Android version as well.

I frequently find myself trying to find which server popped an unread notification, and there's no way to just check the inbox the way there is on the desktop version.

The Notifications tab doesn't quite seem to perform this function - the badge attaches to the Discord icon on the left (iOS; no personal experience with Android) instead. So it seems to me that either Inbox could replace the bell, or there could be a user-selectable option: do you want the Inbox at the bottom, or do you want to stick with Notifications?