Task 5: Tag med kviste - Add kvist details
Changes:
- Added kvist_size (m²) and number_of_kviste fields to geometry form
- Fields only appear when 'Tag med kviste' is selected
- Total kvist area is calculated and displayed (size × number)
- Backend saves kvist data to roof_geometry table
- Area calculation includes kvist area when applicable
- Database migration adds kvist_size and number_of_kviste columns
- Visual feedback with highlighted kvist section in form
