Battery_sim 2.4.0: Average energy value

Track and expose the monetary value of energy stored in the simulated battery, including a new average value sensor and a service to manage it.

New Features

Add a monetary stored-energy value model that is updated on charge, discharge, degradation and resets with the battery.
Expose an average energy value sensor representing the monetary value per kWh of the energy currently stored, with persistence and restoration support.
Introduce a battery_sim.set_stored_energy_value service to manually set the total stored-energy value for a given simulated battery device.

Documentation

Document the new average energy value sensor, how its value is computed from tariffs and efficiencies, and how to adjust it via the new service.

What's Changed

• Introduce value of stored energy and publish average energy value by @dewi-ny-je in #54
• Average energy value by @dewi-ny-je in #55