Refactored AppBar, MenuBar and FilterMenu.
- Restyled AppBar: inverted menu/title order, more compact the layout
- Small refactor of MenuBar, separated Consent and Breadcrumbs into their own files
- Renamed "Settings" to "Units"
- Improved the structure of FilterMenu
- Updated a few help texts
- Renamed some menu entries and their titles to be more consistent
- Improved developer documentation
- Improved filter panel sliding behaviour, decreased its width a bit