Visual:
- Improved 'Open Rentals' design (Card View with proper constraints)
- Improved 'Rental Details' design (view is now scrollable, meaning long strings will always be visible)
- App now matches day/night settings (light/dark mode)
- Add launcher icon

Internal:
- removed placeholder tests
- remove unnecessary permissions (ACCESS_WIFI_STATE/ACCESS_NETWORK_STATE)
- replace findViewById() with View Binding

Other:
- Renamed to 'OpenBike'
