Add a "Maximum Cost per kWh" filter for charging stations

Is your feature request related to a problem? Please describe.

Yes. With the growing diversity of charging networks, prices vary drastically from one operator to another (and sometimes even within the same network depending on roaming agreements). Currently, ABRP plans the fastest or most efficient route, but it sometimes routes me to charging stations that are significantly more expensive than neighboring options, without giving me a choice based on my budget.

Describe the solution you'd like I would like an option in the route planning settings (or under the "Charging Networks" preferences) where I can set a Maximum Price per kWh (e.g., €0.45/kWh or $0.50/kWh).

When planning a route, ABRP should:

1. Prioritize charging stations that fall below or equal to this price limit.

2. Display a warning if a route absolutely requires stopping at a station that exceeds this limit (due to range constraints).

Describe alternatives you've considered Right now, I have to manually check the prices of each suggested stop on external apps, and then use the "Avoid this station" or "Prefer this network" feature in ABRP to force a recalculation. This is time-consuming and defeats the purpose of ABRP's automated planning.

Additional context This feature would be a game-changer for budget-conscious EV drivers, especially during long road trips where roaming fees can spike the price per kWh. Since ABRP already gathers a lot of live data, integrating price caps would make the app even more powerful.