Redesign: room details (outdated)

The new room details dialog. It features a better layout, the addition of the room ID, and the removal of the "leave room" button (which is moved to the overflow menu).

The new overflow menu contains room details, room search, and leave room.

When leaving a room, a popup appears, warning users that they won't receive new history from that room.

Development Tasks

• add overflow menu in header bar
• implement new layout in dialog
• add Matrix ID to dialog
• remove "leave room" from dialog
• disable inputs if user doesn't have the right privileges
• make room ID selectable (for copy/pasting)
• add horizontal padding in header bar buttons
• round dialog corners

QA Tasks

• new room dialog layout looks as expected
• leave room