refactor: server file and function names

app/lib/widgets/choropleth_map.dart

server/lake_relations/added_lakes.txt

server/lake_relations/mjosa_div.json

server/main.py

server/map/__pycache__/add_lake.cpython-311.pyc

server/map/__pycache__/get_markers.cpython-39.pyc

server/map/__pycache__/get_measurements.cpython-311.pyc

server/map/__pycache__/get_relation.cpython-39.pyc

server/map/add_lake.py

server/map/get_measurements.py

server/map/mjosa.geojson