Apply grid operator filtering logic to Netzkosten indicator

[mevionfamos]

Description

The Netzkosten indicator incorrectly displays grid operators that don't serve the selected grid level in specific municipalities. The filtering logic already implemented for Netztarife and Energietarife on Strompreiswebseite needs to be applied to the Netzkosten indicator.

Reproduction Steps

1. Navigate to https://www.strompreis.abn.elcom.admin.ch/map?entity=operator&tab=sunshine
2. Make sure grid level 7 is displayed (default)
3. Hover on Arosa
4. Observe grid operator "Chur" displayed despite only serving grid level 5 in Arosa

Expected Behavior

Only grid operators that declare service at the selected grid level for the specific location should be displayed. This also means filtering out operators with a coverage ratio below 25%.

Additional Context

The filtering logic successfully applied to Netztarife and Energietarife on Strompreiswebseite needs extension to Netzkosten indicator. The information regarding the grid levels is not in the sunshine data but can be taken from the normal electricity tariff data.

Reported by ElCom here and in PELCOMDB-2582

Test Environment

• Ref
• Abn
• Prod