### Add user display name functionality and enhance space management with emoji support and deletion capabilities.
### What changed?
- Added support for user display names, which are now stored and displayed throughout the app
- Implemented emoji support for spaces (projects), allowing users to customize their space icons
- Created a new `AddSpaceModal` component with emoji picker for creating spaces
- Added space deletion functionality with options to move content to another space or delete everything
- Enhanced the space selector UI to show emojis and delete options
